06/02/16 - Guide started. It's only the second day of release (no I don't count the 1 hour on Thursday at 11pm) and as such I haven't gotten very far yet, I intend to update this guide as I go and as I learn new tactics

11/02/16 - I'm close to completion now and have a lot of new things to add. I'll finish the game within the next 2 days then update the guide

12/02/16 - Completed the game last night, updated the class sections. Added an item and combo tactic section that is currently empty. Added new enemy sections that are empty. Will probably update and complete the enemy sections tomorrow

15/02/16 - Updated the first half of the Enemy Guide section dealing with March and April, and elite variants of starting enemies.

23/02/16 - Finished Enemy Guide and Combo Tactics section. Updated Summary section.

25/02/16 - Added a walkthrough that covers the main points and strategies

Commander is the third difficulty of XCOM2. Notable changes are:
1) Enemies have more health than in veteran. This is especially notable in the case of ADVENT troopers who only rarely die in one hit from grenades now
2) Enemies make more aggressive use of their special abilities. Especially notable in the case of ADVENT commanders who use their mark ability to a deadly degree
3) Construction and research takes longer than veteran
4) Soldiers get less health boosts as they level compared to veteran
Will update this section as I learn more about the differences in difficulty

Sorry but this guide is a bit wall of texty. Making jokes or trying to make things interesting isn't really my style, this guide is intended to be as informative as possible, so I don't waste words on information that isn't helpful. Sorry if that's boring, but this game requires patience and effective tactics, and ADVENT can't be defeated through a well developed and diverse sense of humour

Also I feel I should mention, many of the tactics in this guide will be ineffective for Legend difficulty. For instance, enemies have higher HP and there are more of them, so grenade spam won't even carry you through the early game, whereas for commander they are a reliable crutch for the early and midgame that take little effort to use or execute for the results they give. If you are planning to play on Legend then definetly check a Legend guide to learn tactics specific to the conditions you will face on that difficulty setting!

Ranger:

Role: Melee dps, stealth scouting, tanking, burst dps cooldowns at high level, desperation melee dash, anti-sectoid, counter attacks, accurate vs high defense enemies like archons

These guys get shotguns and swords. The shotguns have very high damage and crit for the time in the game where you get them. The sword has equal damage to the shotgun but melee hit chances with a sword are about 50-85% depending on the enemy, with low crit, compared to the shotgun which is typically 100% at point blank, or a few spaces away, plus a very high crit chance against flanked or exposed enemies. Since the shotgun also has more range it makes you wonder why you would ever use the sword. The answer to that is run and slash. Have you ever seen an advent shocktrooper dash across the map and stun your guy? Rangers can do this as well, just point at the enemy and right click when you see the sword icon on the ground, it will show you the direction they slash as well. This move can be used diagionally so if an enemy is taking cover behind a tree or something you can press up against the tree and slash him, protecting yourself from flanking retribution from his friends. If you put yor guys on overwatch and do this, they will shoot the enemy when he runs from cover to reposition, provided they dont burn it on his friends first

Rangers can specialise in stealth moves and combat moves. You may think with the timers that you should be specialising in stealth to reach them faster but this is a trap. You typically move faster if you engage enemy pods as soon as you see them, preventing yourself getting trapped in a brutal firefight where you struggle to make ground. While a stealth ranger is a powerful tool for scouting ahead and preventing an ambush, you typically need all hands on deck to defeat enemy pods as soon as you see them

Rangers rarely get hit in melee by stunners. The current estimate is that melee enemies are 50% less likely to hit blademasters, but it certainly can happen. In one fubar situation I sent my ranger on a last ditch effort to defeat 2 enemy stunners in melee. He won. There's been a lot of other times when stunners tried to hit him but they never did. However, they might have just hit him on the first strike, so it was a gamble that paid off in a desperate situation

At high levels the ranger's aim gets high enough that they have about a 70% hit rate at mid range (about 10 tiles) against an exposed enemy, or 55% against such a target in half cover. This means that in addition to rushing enemies down (which risks pulling more enemies and should only be done in desperation) they can afford to take shots at them from halfway across the battlefield provided you have a means to finish the situation if they keep missing (such as explosives). Rangers cannot be fitted with scopes, but they can be fitted with aim PCS and with the guerilla tactics school upgrade to PCS their aim can be pretty brutal even at a distance

In terms of their abilities however, shsarpshooters, grenadiers and even specialists to a degree can all fill the role of the killer. The only other thing the ranger brings to the table is their ability to quickly reposition using run and gun or run and slash, or their stealth abilities which can be powerful provided the rest of the team can handle the enemy without him

Ranger abilities:
Phantom vs Blademaster: Blademaster is very powerful in the early game, where you have few options for dealing with the enemy, and where the +2 damage goes a long way. I feel phantom is more useful in the late game as you can keep your ranger in stealth to scout ahead for the enemy provided the rest of your team can handle the enemy without him. This is extremely useful not only in timed missions where you have to advance quickly at risk of being ambushed, but also in terror missions where you don't start in stealth but the ranger does with phantom. You can use the ranger to scout ahead, and also to rush out and save civilians provided the civilian isnt a faceless (otherwise it will reveal him and then your ranger is stuck out in the open next to a dangerous enemy. You should drop an evac flare next to the civilian before you try this so your ranger can bail out if it's a faceless)

Shadowstrike vs Shadowstep: Shadowstrike is useful for when you run into an enemy group that you cant finish without help from your ranger. Shadowstep, unlike lightning reflexes in EU, does not trigger but dodge overwatch, it simply causes enemies not to target them with overwatch. You can use it to rush your ranger up to the overwatcher for a shot or a flashbang to break the overwatch. I don't feel like either of these are particularly useful, because rangers get strong close range aim, and the crit isnt enough to be reliable, whereas there are many ways to break overwatch and enemy overwatch is usually very inaccurate anyway if you really cannot break it without moving. I pick shadowstep but really it doesnt matter much

Conceal vs Run and Gun: Now this is a much more difficult choice. Conceal will allow you to continue using your ranger as a scout once per mission if they get revealed, but run and gun gives them an ability that allows them ro reliably eliminate an enemy with their shotgun, compared to their trademark run and slash ability which tends to be very inaccurate and limits your positioning to point blank which can be very risky. I went with run and gun, but I feel like if you're taking a ranger it should be for scouting, because otherwise they are outperformed by every other class

Implacable vs Bladestorm: Implacable lets you move after killing an enemy. You can only use the yellow move though, and you cannot attack. If you attempt to overwatch via the hotkey your game will glitch and you have to load a game to continue. It's useful for repositioning after a successful run and gun or run and slash. It makes run and slash much less risky in the aftermath, but it requires that you kill the enemy or it wont trigger. Bladestorm gives you a free hit once per turn on any enemy that enters melee range. This is very useful when you are using your ranger to ward off melee enemies. I don't feel either of these abilities is very useful, pick whichever. I'd probably recommend implacable but I'm bitter towards it because of the overwatch glitch

Deep Cover vs Untouchable: Deep cover is especially useful when you are rushing in to flank or scout. The enemy will have a close range bonus, but with your ranger hunkered down they are less likely to hit, and theres a high chance any hits they inflict will be for glancing damage. However, you should be attempting to take the enemy down the same turn you engage them, and the enemy is just as likely to target someone else anyway. Also bladestorm will cancel out hunker. Untouchable makes your ranger immune to the next attack. This is wonderful for when you run and slash or run and gun to eliminate the final enemy but fail to finish them or trigger more enemies. Chances are the enemy will target your ranger because they disregard untouchable, meaning your rangers is guaranteed to avoid at least one attack. Rangers only get the untouchable buff after killing an enemy, but it persists until an enemy fires at them, which should be rare if you are killing the enemy on the same turn you engage them. If you use untouchable then try to keep it active by feeding killing blows to your ranger

Rapid fire vs Reaper: Reaper sounds good on paper, but with the terrible range, accuracy and damage of blades, along with the risk of using them and the damage and crit nerf you get from each successive kill with reaper, this really is just the economy fan shot ability. Rapid fire is 2 shots with an aim penalty. Provided your ranger is very close then at colonel rank they won't miss, and can potentially do double damage. This actually gives them a niche as a boss killer as it gives them killing power only rivalled by sharpshooters with lightning hands, quick draw and fan shot all on the same turn. It gives them an additional role to scouting that they really do need. Works amazingly well in conjunction with run and gun

Class Synergy:

Grenadier: Grenadiers work well with every class, but especially killers. Grenadiers strip enemies of their cover and armour, and soften them up, then killers finish the job. Unfortunately rangers are only good at killing at close range which risks pulling more enemies, they lack any pure stopping power abilities til high levels, and while a high level ranger gets decent aim at mid range, a grenadier is still superior for the same role. Rangers focus on running and gunning a flank, or rushing in to slash the enemy, and thus they don't require the cover removing abilities of a grenadier. Thus, rangers have the least syngery with Grenadiers

Sharpshooters: Sharpshooters generally require cover and armour removal to be effective, neither of which the ranger provides. They can go on overwatch to try and shoot the enemy as they reposition, which is useful if you have a deep cover ranger rushing in to flank the enemy position, but you generally want to eliminate the enemy the same turn you see them and sharpshooters should be shooting exposed or half cover enemies, not overwatching

Specialists: Rangers have strong synergy with specialists. The specialists can defend and protect the rangers from a long distance as they make the push. Specialists get strong overwatching capabilities making the ranger flank rush more viable and allowing the specialist to protect the ranger when he fails to connect with his run and slash and risks being flanked as the surviving enemy repositions. Specialists also get abilities for eliminating mechanical enemies who rangers tend to struggle with due to their strong armour. A ranger + specialist strategy is viable, but not as effective as other combinations

Psi Op: Psi Operatives get many useful support abilities that can help save rangers. They can stasis the ranger to protect them if they pull more contact and are left exposed, they can stasis a surviving enemy so it cannot retaliate, they can weaken, finish or mind affect surviving or injured enemies and do so reliably to protect the advancing rangers, and can possess enemies to make them draw fire. A 2 psi op, 4 ranger strategy is a viable fast paced strategy that would be very effective for terror missions, but honestly psi ops synergise well with everyone and there are more effective combos

Ranger: A pure ranger squad can take the aggressive push strategy and carry it forward. Even if your rangers are charging in at the enemy and pull new contact, they will all be rushing in together so will be in a better position to support each other. Overwatch is a wasted enemy move, and with untouchable they have high survivability. You will need to carry grenades, especially acid or blue screen grenades for enemy mecs, and the WAR suit will give them cover blowing, shredding and long range options. And when things go fubar they can all just conceal and reposition to regain the momentum. The only time I can justify using multiple rangers is with a pure ranger squad or a range/psi op squad. It really is a very dangerous style though, and timers really arent all that difficult to require such a thing

Summary: The close range fighting style of rangers is very risky in Ironman due to the risk of pulling an additional pod of enemies. Run and Gun, along with rapid fire gives the ranger a kind of burst stopping power vs strong enemies in dangerous situations. Rangers can really pull through in a desperate situatuion, but they could also damn you due to the close range requirements of their abilities. As every other class fulfills the role of killer as well as if not better than a ranger, I cannot recommend taking them as combatants. Snipers can achieve burst damage on a cooldown with their pistol cooldowns, and sustained damage with their sniper rifles with an elevation bonus and can do so from a distance without pulling more enemies. Specialist arent far behind rangers in damage (until the ranger gets run and gun and rapid fire) but unlike rangers can provide fairly reliable long range fire support.

Rangers are most effective in March as blademasters to eliminate surviving enemies. This is because you won't immediately have a guerilla training school and probably wont have a strong roster til April.

However, after that the rangers are for more effective as scouts, therefore I would recommend you always build them as scouts, they're just too risky and replaceable as killers by every other class. Rangers do outperform squaddie specialist and snipers in terms of killing power but they fall behind too fast. Considering that using a scout means sacrificing a squad space, at least until your ranger gets conceal, and eventually rapid fire, you should wait til you have squad size 1 at least before you bring one.

Rating: 8/10 (single scout ranger)
6/10 (combat rangers post-March)

Specialists:

Role: Healing support, limited control vs mech enemies, executing <3HP enemies, fairly accurate mid range DPS, long range objective hacking, skullmine intel farming in mid-late game

The support class of the game. Their starting ability is pretty bad, I'd generally recommend overwatch as a defensive tool over aid protocol. The only time I see it being useful is when one of your soldiers is flanked and cant get to safety, or when you need extra safety for a VIP. They also get remote hacking.

Remote hacking allows a specialist to reach hacking objectives more quickly. They can open cell doors for scientist/engineer rescues from a distance or even through open windows. You can also hack the scanner towers but this is typically more difficult. Hacking has a chance to give a special bonus which can persist outside of the mission, such as faster construction or scanning. It can also grant something useful for the ability like temporary buffs to your squad, or a mind control on an enemy, potentially enabling you to completely change a FUBAR situation. When hacking towers it can also causes a negative effect to trigger on failure, like temporary enemy buffs, or reinforcements. One thing to look out for is the hack bonus that permanently increases your specialists hacking ability. Aside from levelling, gremlin upgrades and the skullmine, this is the only way to improve hacking and can snowball into even easier hacks. A specialist with extremely high hack can reliably trigger amazing specials on a hack. Early on the risk of a negative effect is very high, you should generally only try to hack a tower right before ending the mission so you don't need to deal with the negative consequences when you probably fail. However, summoning enemy reinforcements can get you more exp and corpses

Specialists aim is abysmal initially, but assault rifles arent far behind shotguns, sniper rifles and cannons in damage, and at higher levels with scopes and aim upgrades can pull off reliable shots at high range, enabling you to finish enemies exposed, injured and shredded by grenadiers without needing to advance far. They lack the sheer stopping power of snipers, grenadiers, and rapid fire rangers though

Abilities:

Medical protocol vs combat protocol: While healing protocol is very useful for a medic specialist, the combat protocol is just too good to pass up in the early game. It can be used twice per mission and never misses. It does 2 damage to organic enemies, allowing you to reliably finish wounded enemies, especially codex who have teleported into cover, or to break enemy overwatches (they break on damage). They also hit robot enemies twice and ignore their armour, making them amazing for early mechs and turrets. In the late game specialists are fairly accurate with their rifles, and the ability to heal someone at a range can be very powerful, considering respeccing into medical protocol in the late game

Revive Protocol vs Haywire Protocol: Revive Protocol allows you to revive a soldier once per mission, amazing for when you just cant finish a dangerous enemy like that enemy stunner and someone gets KOd. You can also cleanse a sectoid's mind control without a flashbang, which is great when you used your flashbang or no one is in range to flashbang the sectoid. It also removes panic but I feel this is wasteful unless the situation is dire. Later in the game your soldiers rarely panic, get mind controlled or stunned, but you face many powerful enemy MEC units. To reliably disable or hack them you require the gremlin upgrades and skullmine tool which just arent available til mid-late game, and by then you probably have an AWC. I suggest you take revive protocol initially, and respec in the AWC to haywire protocol around July

Field Medic vs Scanning Protocol: Scanning protocol works like the battle scanner, but the battle scanner can be used by anyone, and scanning protocol breaks stealth whereas battle scanners do not. The triple medkits is extremely useful if you can spare the time for some first aid. Medkits also cleanse poison, including the deadly chrysalid venom

Covering fire vs threat assessment: Due to the high speed nature of the game I feel overwatch is generally wasteful. I usually take covering fire, for the situations where I am unable to remove an enemy's cover, as the overwatch fire will trigger if they try to do anything and will be much more likely to hit than a 30% shot vs full cover. Pick whichever you like though, neither is very useful

Ever vigiliant vs Guardian: Guardian can be powerful in those fubar situations where you had to put your specialist on overwatch, but you really shouldnt be getting into those situations. Ever vigiliant in combination with covering fire can slow you to rush your specialist up to a flank and be almost guaranteed to hit if the enemy tries to run, or any of his friends who try to take a shot. Again, I dont feel either of these is very useful though

Restoration vs Capacitor Discharge: The mass heal and restoration effect is amazing in a fubar situation, but you shouldnt be getting to that point to begin with, and the key to not getting into such a dire situation is to kill the enemy fast. Capacitor discharge gives the specialist an ability akin to a one time void that can really turn the situation around when your ranger triggers another enemy group who rush in but cluster for the capacitor discharge. Either of these is a powerful ability, but I lean towards the latter

Specialists are excellent candidates for EXO or WAR suits as the built in rocket launcher gives them additional AoE and cover blowing capabilities. They don't require blaster or shredder cannons as they are already strong at range at a high level

Class synergy:

Ranger: Specialists synergise well with rangers as they can support them from a distance. Rangers lack armour shredding capabilities so a specialists haywire ability is useful in a ranger heavy squad for eliminating MECs, although grenadiers synergise better for that

Grenadiers: Specialists dont synergise well with grenadiers in the early game, as they lack the aim and damage to follow through on the grenadier's cover blowing abilities. They synergise much better in the late game as specialist can reliably hit for respectable damage at a range with their plasma rifles. Grenadiers also specialise in bringing down mecs with their shredder, and specialist specialise in bringing them down with haywire protocol. Consider using grenadiers to finish MECs if the haywire protocol fails, this allows you to do things like gambling with trying to take total control over a MEC rather than simply shutting it down

Sharpshooters: As sharpshooters generally attack from a range, they are the least likely to require a specialist's help as they are the least underfire. As sharpshooters lack any armour shredding capabilities though, a specialist can shut down MECs with haywire and buy the sharpshooters more time to kill them

Psi op: Specialists don't synergise well with Psi Ops. They are both primarily support classes. The Psi Ops have few destructive capabilities and focus primarily on mind control and crowd control, but specialists lack the stopping power to follow through unless the target is exposed

Specialists: As with psi ops, a specialist heavy squad isnt viable. Their abilities are primarily support, limited anti-mec, damage vs exposed enemies, and long range objective hacking. A spec heavy squad would be limited to overwatch camping, which is awful in a game that incentivises a rapid rate of progress

Summary:

Specialists are effective support personnel. Their early abilities help out massively in the early game, but become less useful in the late game. They can pull their weight at a high level but only with a grenadier to soften and expose enemies for their plasma rifles. Colonel supports get a one time panic button ability that can completely turn around a dangerous situation, and they can be extremely useful vs strong enemy mecs, but I feel like psi operatives do everything a specialist does and does it much better.

Specialists level faster than every other class and are effective for getting squad size early. They are also very useful for getting the hacking objectives quickly. I recommend you bring one along, its good to get one levelled quickly, they can really save you on the hacking objectives, their combat and revival protocol are extremely useful in the early game, and their aim will pick up to near sniper level quite fast due to their rapid rate of progress. Their damage really isnt that bad once their aim improves, but they only have one effective late game damage move, and it's limited to one use per mission, and pretty much outclassed by a psi operative's void. I'd recommend ditching them for psi-ops in the late game, but you should definetly make use of them in the early game

Rating:
7/10 in March
5/10 post-March

Grenadier:

Role: Reliable AoE damage, shredding, tanking, inaccurate mid range moderate dps, accurate damage cooldown, AoE damage cooldown, cover destruction, softening groups, rupture, control with special grenades

The only class that can potentially do everything when levelled and use properly. These are incredibly useful soldiers to have. Since enemies don't drop weapon fragments anymore you only risk losing loot items. Loot drops rarely, and you usually wont finish the enemy with your grenadiers anyway.

They can OHKO troopers in veteran but aren't quite so OP in commander due to the extra point of HP troopers get which enables them to often survive grenades. Grenadiers carry grenade launchers which launch grenades much farther than usual, and get a free grenade as well.

Their primary uses are for cover blowing, armour shredding, AoE killing or softening up groups of enemies, for finishing injured enemies, for detonating vehicles (usually requires too grenades, but if you see a vehicle set on fire with gunfire consider hitting it with a grenade to destroy it if an enemy is taking cover on it).

They can blow holes in walls to reach objectives or escape from a sticky situation, and their grenades destroy floors, causing enemies on higher levels to suffer additional falling damage and lose their height bonus. This is always a OHKO on rooftop turrets. Be warned, if you destroy the floor of an extraction point on a building roof then the extraction point gets moved somewhere else which you might not be able to reach in time, this can occur with fire as well!

Grenadiers also get gatling guns which do slightly higher damage than the other primary weapons but with abysmal accuracy. This can OHKO troopers at full health, and are very useful for dispatching the stronger enemy types. They get less ammo than assault rifles so consider getting ammo loaders or clip expanders ASAP. Aim PCS and scopes can offset their accuracy penalties and bring them close to snipers. Remember that you can reload and fire in the same turn provided you dont move and you use reload as your first action

At higher levels they gain an ability on a long cooldown that uses 3 ammo but always hits, it is exceptionally useful for eliminating Codex and the special enemy that always teleport after being hit and thus are resistant to cover removal. It's also a reliable killer move or armour shredding move. They can also gain an ability that hits multiple targets in a cone for 3 ammo with the usual hit chances, but can target enemies through walls and high cover obstacles, enabling you to hit enemies who cant even see you!

At corporal, grenadiers get to choose between better armour, or shredder ammo. Both are good choices but I feel, in a game where aggression is rewarded and defensive play is punished, the ability to weaken and damage strong enemies like mechs is just too good to pass up, whereas if you take the defense bonus it just means the enemy will kill everyone else first. I've yet to get one of these guys to sergeant, because I use them to blow cover a lot, and that usually means they feed kills to everyone else. They are excellent for finishing stubborn enemies. I recommend you bring 2 or 3 of these, they'll really push your offensive forward and keep the momentum going! I actually feel like they're a bit OP but early on in the game they're really the solution to everything, and they're so good even at squaddie rank!

Grenadiers level the slowest of all, require more than twice as many kills as a specialist to level. Couple this with the fact that they are usually used to soften enemies and blow their cover for the killers to eliminate, they tend to lag behind in kills as well unless you are using many of them to AoE nuke the enemies. Since their abilities are amazing at higher levels you should try to feed kills to these guys to let them level up with the rest of the squad

Abilities:

Blast Padding vs Shredder: Blade padding is the most useful ability in the early game, because few enemies have armour, grenades are sufficient for elimating single armour points, and grenadiers have terrible aim initially. You can respec to shredder ammo in the mid to late game when you have an AWC. The single point of armour may not seem like much, but it could save your grenadiers life, and when you consider how hard these guys are to change and how brutal the early - mid game can be it really is worth it. You should definetly switch to shredder in the late game, the single point of armour won't make a huge difference, the shredder ammo shreds 3 points of armour, thats higher than the plasma grenades 2 armour, outclassed only by acid grenades with their 4 armour shredding. When combined with bullet storm it enables you to reliably destroy armour and damage strong late game enemies like andromedon, gatekeeper, sectopod and the special enemy

Demolition vs Suppression: Grenadiers already have cover blowing capabilities, and grenaders are far more reliable than demolition with the ability to remove cover in an area rather than a single cover while also damaging enemies and shredding their armour. However, in the early game you probably have few grenadiers and lack the third grenade ability. I still feel that suppression is better for when your guys miss too many 90% shots and you need a way to protect your soldiers from the return fire. If you suppress a flanked enemy it will likely run and then theres a fair chance theyll be hit by the suppression. An enemy who isnt flanked who chooses to stay still and fire will likely miss due to the -50 aim penalty imposed by suppression. You probably wont use either of these abilities very often though due to the aggressive nature of the game

Heavy Ordinance vs Holo targetting: HT is very useful in the early game when your soldiers aim is abysmal, but it doesnt trigger on grenades and requires your grenadier to waste time firing. HO is just so much more valuable, not only do you get an extra grenade, which can mean 2 acid grenades if you placed one in your second grenade slot, but if you are using many grenadiers you could put a gas bomb (poison lowers movement, and also lowers aim by 30) in the second slot and get 2 of them, increasing the support capabilities of your grenadiers

Volatile Mix vs Chain Shot: definetly VM. Grenadiers have bad aim already without the aim penalty of CS, CS would be only viable to short range which carries all the risks associated with rangers. VM increases the damage and range of your grenades, allowing you to much more easily AoE down groups of enemies, afflict multiple enemies with acid, or flashbang many enemies to disable their abilities for a turn. You could also flame multiple enemies to stop them using their abilities, and use a possessed codex to drain all their ammo. Flamed enemies cannot reload so they are essentially crippled for 3 turns unless they have a melee attack. When you get grenadiers to Captain rank they become incredibly broken, able to effortlessly eliminate large groups of enemies with a mass bombardment by multiple grenadiers

Salvo vs Hail of Bullets: Be sure to read the fine print on Salvo. Does not end your turn. What this actually means is your grenadier uses his blue move to launch a grenade and can then reposition if he needs to on his yellow move. Hail of bullets has a long cooldown but considering the terrible aim of the grenadiers it's amazing for shredding armour or eliminating weakened enemies without having to waste grenades. It also wonderful for codex and the special enemy who will likely teleport into cover after being hit with a grenade, but can still be reliably hit using hail of bullets. At high level with the aim PCS

Saturation fire vs Rupture: They're both pretty amazing. Psi ops can apply rupture, but you usually want to be casting something other than insanity, and void isnt reliable for rupturing enemies. A grenadier with upgraded aim can reliably rupture exposed high health enemies. This works extremely well in conjunction with the sharpshooter's quick draw - lightning hands - fan shot combo as each of the 5 pistol shots benefits from the extra 3 damage, enabling the sharpshooter to potentially do over 40 damage on a single enemy! Saturation fire is also very good as, like Psi Lance, is can fire through walls and obstacles at enemies who the grenadier cannot see. It has a wider range than psi lance, but does less damage on average and uses the grenadier's ordinary aim. This attack sometimes shreds cover. I'd like to recommend rupture here for the sharpshooter combo, but there's been so many times I've seen an awesome chance to use saturation fire to finish multiple enemies, only to realise the grenadier in position to do so had rupture. Either is good but I line towards saturation fire, it's more reliable than rupture, and I prefer reliability over potential massive sectopod murder sharpshooter carnage

Class Synergy:

Note: Let me just say this now, grenadiers synergise well with everyone. Their cover blowing, armour destruction and AoE damage enables killers to eliminate the enemy reliably from a range, and this is something every other class benefits from. I don't want to keep repeating this so here it is

Rangers: Rangers specialise in rushing around enemy cover to shank them, or fire with run and gun, this they benefit less from the cover blowing capabiltiies of a grenadier than other classes. However, the risk with rangers is of them ranging out too far and pulling more enemies, and the cover blowing enables the ranger to fire accurately from 3-4 squares away which could be the different between finishing the enemy pod, or accidentally pulling 2 more! Bringing a lone ranger can allow you to scout ahead as you move your grenadiers up. While it means sacrificing a squad space, grenadiers are so powerful anyway that they can probably handle the enemy by themselves, and as grenadiers are so hard to train you really want to avoid those ambushes. Rangers can phantom at corporal so you can rush them ahead and treat them as expendable on terror missions, or equip the ranger with battle scanners to trigger faceless without breaking stealth so your grenadiers and sharpshooters can kill them as they advance. They can also run around saving civilians from stealth while your grenadiers advance and clear the enemy

Specialist: Specialists level fast and get decent aim at high levels. Grenadiers can remove cover while the specialists take the kill. You can attempt to hijack Mecs temporarily with the specialists, and kill the mec with your grenadier if it fails

Sharpshooters: These synergise especially well with grenadiers. Due to their poor aim and lack of any single target burst damage, grenadier squads struggle to take down strong enemies in the late game. Sharpshooters have amazing burst cooldowns at high levels, and at low levels their sniper rifles are deadly accurate against exposed enemies if you park them on a roof. Grenadiers are the ultimate AoE damage, cover shredding and armour shredding masters, and sharpshooters are the ultimate single target killers, so they work exceptionally well together!

Psi operatives: Specialists on steroids basically. Psi operatives long range damage capabilities with their AR arent far behind snipers when you take the snipers cooldown damage out of the equation. Their stasis ability allows them to paralyse powerful enemies like sectopods, archons, andromedons or gatekeepers if they cannot finish them that turn, and the psi operatives other powerful abilities are amazing in the event that you get ambushed. I'd consider swapping out sharpshooters and specialists for Psi Ops in the very late game, Psi Ops really are just broken

Grenadiers: A grenadier heavy squad is overpowered. When they're all at captain level with their high damage high AoE grenades with upgraded launchers and the plasma grenade proving ground project, both of which require only a muton autopsy, they can just advance directly towards the objective and obliterate everything with half their turns! With 6 bullet storm cooldowns you will never miss a shot, and laugh at the enemies armour and cover. The only problem is their difficulty in eliminating strong enemies like sectopods and andromedons on their first turn. They miss a lot til they get bullet storm, and these enemies have so much health that they'll probably end up getting a turn unless you can CC them with a psi op or specialist, or DPS them with a sharpshooter. They also have to advance using blue moves or risk being too far out of range of the enemy to salvo them on activation, and dashing them tends to trigger multiple enemy pods. They take forever to level up and even one loss is a huge deal, so reckless advancement is more dangerous with grenadiers over any class except psi op who are the hardest class to raise. If you want a grenadier death squad, at least bring a phantom ranger to scout ahead and allow them to safely dash in single file towards the objective. I'd also recommend a stasis psi op in the late game or a haywire protocol specialist for the sectopods

Grenades:

You really need the proving grounds early to draw out the full potential of grenadiers, and the various grenades you can get give them massive versatility

Gas: Poison applies a -30 aim and a movement penalty (thanks to AfroDuck for the information!). They're slightly more effective than flashbangs, but a smaller range and leave a dangerous gas cloud behind that could obstruct you

Fire: Damage is less than acid, and they don't shred armour. However, burning enemies have all their abilities disabled and cannot reload. Flashbangs have a wider range and also debuff aim, but only last 1 turn and don't do damage like fire does. Opening with a fire grenade will cripple enemies

Acid: Doesn't destroy cover, but removes 1 extra point of armour and causes the enemy to take 3 damage at the start of their turn til it wears off. This means every enemy hit by this grenade will take 3 more damage when you end your turn, so you can ignore any acided enemies with 3 or less HP. Acid doesnt destroy loot, but good luck reaching it if its in the middle of the acid pool

Flashbang: These apply a -20 aim penalty and shut down abilities for a turn and break mind control. Useful vs early sectoids, but outclassed by fire grenades for ability shutdown and gas for move and aim debuffing.

Smoke: These are strong but I try to avoid giving the enemy a turn to fire. The smoke wont be much use unless your men are clustered together, which can be dangerous later in the game unless the enemies have been burned or flashbanged

Plasma: Replaces ordinary grenades. You only need to buy this once at the proving ground. Does 7 damage, always destroys cover, and has a large radius. Since you only need to autopsy a muton for this its ridiculously OP for when you get it

Blue Screen (of death): Supposedly effective against mechanical enemies, I havent tried it. Would be nice if it disables their abilities. I'll test it soon

Summary:

The most powerful class in the game aside from psi ops, they can easily storm through the level and AoE enemies down. They get their plasma grenades and improved grenade launchers early, and acid grenades can OHKO advent soldier squads in the late game due to the 3 acid damage they will take at the start of their turn. In the late game their single target damage suffers, so they require either sharpshooters for their insane burst damage, or psi op to stun the enemy so you get another turn to finish them. Due to their insane AoE stopping power, you can sacrifice a squad slot for a phantom ranger to scout ahead and allow a rate of rapid advancement towards the objective, just be sure to travel in single file along the exact path of the ranger so you don't accidentally pull new enemies through a window or something. I expect grenadiers will be nerfed very soon, because aside from ther lack of single target burst damage or crowd control there's nothing they cant do by themselves. They are imo second only to psi ops, but even a pure psi op squad would struggle with timers due to their lack of sustained damage against enemies in cover with armour, since the psi ops only 2 strong attacks have long cooldowns

Rating:
8/10 - March/April
10/10 - May-June (assuming Lieutenant/Captain rank) or 7/10 at Sergeant or less
9/10 - July+ (assuming Captain rank) or 6/10 at Sergeant or less

Sharpshooter:

Role: Single target massive mid-range accurate DPS, AoE cooldown, single-target burst damage cooldowns, counter attacks

Snipers have some insane aim bonuses. With a sniper on a roof, with a Scope, or a couple of level ups its not unusual to see 100% hit chances against exposed enemies. Thanks to squadsight they can target any enemy that another squad member can see, provided they themselves have a clear line of sight. The downside is they can't move and fire their sniper rifle at the same time. They can move and fire their pistols, and initially there's no drawback to doing this, but if you pick up quickdraw at Lieutenant rank you will once again want to keep them still. Pistols do little damage, but with the insane accuracy of snipers they often get 80-90% chance to hit enemies in half cover at a medium distance, or 100% while on a roof or vs exposed enemies. As such they are excellent for finishing weakened and exposed enemies reliably in the early game

Their sniper rifles do respectable ranged damage, and with extremely high accuracy, but their accuracy increases the farther they are from the group so they tend to lag behind when using it. It's a powerful early game weapon, but when you pick up quickdraw the pistol can match the sniper rifle in damage provided they stay still and fire twice.

You should always try to get the elevation bonuses on these guys early on, it's just one more 100% reliable way to finish grenaded enemies who are out of cover, and your hit chances against enemies in cover are pretty good too. Before you get quickdraw you should really be trying to keep them at a distance and elevated for the maximum aim bonus. This makes them poor on missions where you must reach an extraction point as you have to keep moving them up with the group and they will suffer aim penalties to their sniper rifles. After they reach lieutenant you can start bringing them on extraction missions as well, just be sure to always move them into full cover, even if it means passing up on an overwatch, so they can fire twice next turn if necessary

Abilities:

Long Watch vs Return Fire - Overwatching is good for ending your turn if there are no active enemies. It gives you the opportunity to fire on any pods that patrol into view during the enemy turn and then next turn you have a full move against injured enemies. This will only help if you didnt move or fire your pistol last turn though, otherwise you will just pistol overwatch. Return fire lets your sniper return fire if the enemy fires in their general direction. They don't need to be targetted directly. If someone is stood next to the sniper and the enemy fires the snipers will make a ducking animation because it was nearby, then return fire will trigger anyway. I don't like to give the enemy a chance to return fire so I rarely saw this activate, but its very helpful when you mess up a pull or accidentally trigger another enemy group. It's also very effective when you have flashbanged and burned enemies, as they are unlikely to hit but will still trigger return fire. I don't consider either of these abilities very good so pick whichever

Dead Eye vs Lightning Hands - This selection decided whether your sharpshooter will be a sniper or a pistolier really. Sniper rifles suffer severely in damage as new options become available, and the pistol cooldowns that snipers get are extremely powerful. Deadeye allows sniper rifles to remain viable, but due to the aim penalty you will need a scope, aim PCS and elevation bonus to ensure guaranteed hits. It really comes down to whether you prefer pistols or sniper rifles but consider this. Specialising in the sniper rifle will allow your sniper to benefit from squad sight, and can stay at a distance in bad cover and never need to move provided they have a clear line of sight. But pistols allow the sniper to deal very high damage, keep up with the squad, and easily reposition to get an angle though at the cost of some damage. Considering how the game incentiveises aggressive rushing, and on extraction missions you need the squad to make a lightning strike together and evac fast, the sniper rifle was just far more suited to Enemy Unknown compared to this one where you cannot afford to stop pushing forward. Lightning Hands is a 50% extra damage cooldown that doesn't cost a move, I suggest you take it if you want your sharpshooter to remain useful

Death from Above vs Quickdraw - This is where sharpshooters really become viable. With quickdraw and lightning hands your sharpshooter can essentially fire 3 times, and split the shots between targets or focus on one. This still requires your sharpshooter to stay still, since quickdraw uses up the blue move. You cant uses quickdraw and then fire a sniper rifle as the sniper rifle requires both moves to fire. However, you get comparable damage output with a pistol and quickdraw to a sniper rifle shot. Quickdraw enables the sharpshooter to travel with the squad and keep up respectable damage, provided they dont move. The general idea is to have your sharpshooter fire both pistol shots, and then on the next turn dash up to keep pace with the squad. With lightning hands you can fire 3 times, potentially generaing more single target damage than anyone else in the squad at this time. Death from Above is nice, but sniper rifles are a relic of Enemy Unknown and not suited to the fast paced style of XCOM 2

Kill Zone vs Faceoff - Once again it's sniper rifles vs pistols. I've made it clear where I stand on this. Faceoff can be fire after quick draw, so you could potentially open with a pistol shot, use lightning hands, then finish with Faceoff. Alongside the grenadiers cover removal, armour shredding and softening capabilities with their grenades, the quickdraw LR faceoff combo is a monster

Steady Hands vs Aim - Again, you need to be aggressive in this game. You should always be firing on the enemy, and steady hands bonus to aim and, more importantly, crit will further boost your damage dealing capabilities, compared to aim which requires you to forego your attacks and gain additional aim that your sharpshooter aim beast doesnt even need. Neither of these abilities is all that good though, pick whichever you like

Serial vs Fan Fire - Serial would be a beast if not for turn timers. It's still awesome for the story missions in wide open areas, and for blacksites. I can't say it's worth raising a seperate sniper just for that though, and fan fire is one of the most overpowered abilities in this game. When you rupture an enemy, the extra +3 damage applies after armour is taken into consideration. Meaning if you are firing at a sectopod and for whatever reason you couldnt shred its armour, you might do 1 damage normally, but with rupture each shot does 4 damage. If you assume it's armour was shredded then, with the beam pistol damage of 6-8, if we assume the average shot is 7, plus 3 from rupture, then the average shot is 10 damage assuming you never crit. This means, provided every shot hits the target and doesnt crit, you can expect a quickdraw, lightning hands, fan fire combo to hit for 50 damage. 35 without rupture. Get fan fire

Class Synergy:

Ranger: Stealthed rangers can spot targets for your snipers to fire at. It's pretty good for terror missions

Specialist: Pistol sharpshooters are usually quite close to the action so can benefit from the standard defensive abilities of a specialist. Pistols suffer vs armour, but if for some reason you can shred the armour with a grenadier then specialists can handle the MECs. I wouldnt recommend this combo though

Grenadier: Grenadier and Sharpshooters were made for each other, though grenadiers synergise well with everyone. Grenadiers can break armour, remove cover and soften enemies. Enough grenadiers can AoE down all the enemies but with the sharpshooters multiple pistol shots and faceoff they can save you grenades, and their faceoff range is much higher than grenade radius as well. Most importantly of all, Grenadiers lack single target burst damage capabilities, but snipers can burn down those tough archon and sectopods. If you have a grenadier with rupture, you can perform the devastating Sharpshooter Fanfire Rupture Kill Combo (SFRKC) that, as far as I'm aware is the most devastating single target combo in the game

Psi Op: Also able to apply rupture via insanity. They can also apply mass rupture via void but its unreliable. Void + Faceoff combo is a very powerful AoE clear but you will probably need to grenade them first to clear cover and armour. What your sharpshooters can't kill, your Psi Ops can stasis so you get another turn to finish the job.

Sharpshooters: Taking multiple sharpshooters is a valid strategy. You can mass AoE with faceoff or burn with fanfire. Unfortunately fanfire is only accessible at colonel though. Sharpshooters can get by without the cover blowing capabilities of grenadiers, but their pistol damage suffers severly against armoured enemies. Even if you plan to use a lot of sharpshooters, at least bring a grenadier or two with acid grenades to clear armour, and a stealth ranger to scout ahead or you just wont make those timers due to how much sharpshooters really must stay still for their quickdraw/rifles. If you really want to use only sharpshooters then make getting dragon and bluescreen rounds a priority, they ignore armour vs the correct enemy types, or bring AP rounds so you dont need to worry about matching sharpshooters against the correct targets

Summary:

Sharpshooters are pretty bad early on. Until their pistol abilities develop they are forced to camp on rooftops with their sniper rifles and just cant keep up with the group. You'll be frustrated constantly be awkward line of sight angles or by having to dash your snipers to keep up and evac on time. However, at Lieutenant they get comparable damage to the other classes with higher accuracy, at Captain their AoE clearing abilities become a match for grenadiers, and at colonel they become death incarnate. Because experimental ammo/rupture is applied with every shot they can reach some insane levels of damage with their multiple pistol shots, but primariyl against single targets. Grenadiers outperform them early on, but sharpshooters pull their weight at Lieutenant/Captain, and are crucial for the late game super enemies unless you are using Psi Ops to CC them

Rating:
4/10 at Corporal or lower
7/10 at Lieutenant/Captain
8/10 at Colonel OR with dragon/bluescreen rounds
9/10 at Colonel with dragon or bluescreen rounds, but bring no more than 2 you need grenadiers and psi ops for shredding/rupture/stasis/AoE softening/cover destruction to really make them excel

Role: Reliable low-moderate damage on cooldowns. Accurate mid range moderate damage. Permanent limited mind control. Reliable single target CC cooldown. Reliable single target protection cooldown. Limited tanking cooldown. AoE damage/CC cooldown. Self-healing moderate damage cooldown. Powerful single target unreliable CC cooldown. Rupture.

Well, Psi Operatives are a bit hard to explain. They have a mix of damaging, crowd control and utility abilities

Like Specialists, PO carry Assault Rifles, which do respectable damage with decent accuracy. They can kill enemies exposed by grenadiers at a range fairly well at high level

Unlike most classes they dont rank up through killing, but through training in the Psi Lab. This not only teaches them new abilities, but increases their "rank" allowing them to gain the usual upgrades. Statistically a max level Psi Op is a Major Specialist. It may seem like a good idea to train PO til they get stasis and min control, then switch to another one, but remember that they will have low stats unless you get them up to "Magus" rank, which requires most abilities unlocked

As such, this is the only class you cannot conceivably rush out. If you can get a Psi Lab by late May or early June you can expect a couple of Psi Operatives at Magus level by late August. Which is just as well since you can get by just fine with Grenadiers til the late game anyway at which put PO synergise very well with them

Abilities:

Soul Fire and Stasis: You get one of these when your Psi Op finishes initial training.

Stasis: Stasis always works, and essentially forces one enemy to miss a turn. You can have everyone else attack a group of enemies, killing the weaker enemies and wounding the stronger one, and then if you cant finish him just cast stasis with your Psi Op and make it miss a turn. This is excellent for late game enemies like Sectopods, Andromedons, Archons and Gatekeepers. It can also save you from a codex mass disable since those things are a pain to kill. With stasis shield you can do this to allies, which is good if you rush one forward and activate a new group of enemies and need to save them.

Soul fire: Does 4-6 damage guaranteed, it cannot miss, it bypasses armour and it cannot dodge graze. It's kind of like a better version of combat protocol, initially, but if you learn soul steal as well then it causes your Psi Op to heal 3 HP

Insanity: The move that sectoids use. Applies a random mind effect on enemies, which can include disorientation (flashbang), panic (which can cause enemies to shoot each other), and a 2 turn mind control. When I cast this as a magus with an alien psi amp it always seems to mind control. If you learn schism insanity does 2-4 damage, following the same rules as soul fire, and also applies rupture. If you dont know what rupture does, ask a gunslinger sharpshooter (it makes every attack do 3 extra damage, which includes pistol combo attacks!)

Inspire: Give an ally a free turn. Great for when your Psi Op can't get a line of sight, or when you need a certain ability desperately.

Solace: A passive that removes all negative mental affects from nearby allies. This won't stop the enemy from attempting mental affects on them. I've seen enemies mind control my guy, only for it to be insantly removed by the psi op standing next to him

Sustain: Passive that makes it so if the Psi Op is killed they have stasis cast on them and are left with 1HP. This can only happen once per mission so on your turn put an evac point on your Psi Op, have him cast a parting spell, then evac him. They're too valuable to risk. This ability is awesome for dealing with enemy crit through full cover from across the map BS

Fortress: A passive that makes your Psi Op immune to fire, poison, acid and explosives. It will not make them immune to falling damage if their roof they are stood on gets blown up, nor will it protect their cover from destruction. Other than that it makes it much safer to cluster them when andromedon, snakeladies, MECs or mutons are in the area, and you can rush them through your own acid/fire polls to grab loot or objectives. If you think they are safe from melee enemies while stood in acid though, think again, they'll rush straight in to get you

Fuse: Detonates an enemies explosives. Works on corpses. More importantly, you can strip an enemy of his explosives if your men are clustered together. The detonation will damage the enemy, any nearby allies, and also destroy his cover. I feel like there are better spells to cast, but an enemy grenade can put your whole squad in the sickbay and ruin your day if you cant kill them first

Domination: Takes permanent mind control of an enemy for the rest of the mission. Can only be used on organic enemies. Can only be used once per mission. If it fails then it goes on a 4 turn cooldown and you can try again but once it works you cant use it for the rest of the mission. At magus level and with an alien psi amp, the only things that could resist it in my game where Codex, and even then it was a 90% chance. You can actually dominate andromedons with this but beware, if the andromedon is killed by an enemy and its suit takes over you lose your control over it! If you can grab a Codex then even better, then you can disable all enemy weapons. Since burning enemies cannot reload you can use it alongside a grenadier's fire grenade to cripple enemies. You can dominate shieldbearers and use them to shield the group, but they only get one use of the ability. You can dominate enemies and leave them in the open to draw fire

Beware, using this ability might cause the dominated enemy to spot and activate more enemies!

Null Lance: Hit every enemy in a line for 9-14 psi damage. This is a heavy hitting attack on a 4 turn cooldown. It cant hurt your people but cannot damage the scenery. It always hits provided you can target the enemy with it, making it an excellent kill move. It's generally quite hard to line up the shot on multiple targets so if it happens then consider yourself lucky. This is a OHKO against most enemies, and very effective for burning down strong enemies

Void: Does about 7 damage in a medium AoE to all enemies caught in it. Your Psi Op needs to be able to see the impact site so you would think it's an economy grenade. Void ignores all armour though, it doesnt do scenery destruction, but organic enemies caught in the blast have about a 50% to suffer insanity. And when I say suffer insanity, I mean your Psi Op starts casting insanity as well on the enemy. As usual, insanity does 2-4 more damage, applies rupture, and has a high chance to mind control. Imagine damaging a group of enemies for 10 damage, applying rupture, and mind controlling them all in one move. This is an excellent opening move

Class Synergy:

Rangers: Inspire can give a ranger another shot to eliminate a missed enemy, or to pull back when they put their foot in it. Stasis can save them from enemy retaliation and allow them to fight more aggressively. Mind affecting abilities can be used to cripple enemies while your ranger clears up

Grenadiers: Grenadiers lack burst damage. You can cast stasis with your psi ops at the end of your turn on anything your grenadiers didnt kill and finish the job next turn. You can give a grenadier another action to do more AoE damage or flashbang an enemy group you accidentally pulled. You can open with void/insanity to rupture and wound enemies, then start the grenade bombardment which will get +3 extra damage on any targets who were ruptured. You can burn high HP enemies with null lance, which is also pretty awesome for dealing with those pesky Codex and the special enemy

Specialists: I feel like Psi Ops are just better versions of specialists. If you've got Psi Ops, you don't need specialists. Stasis is more reliable than haywire protocol. Specialists are left only with their healing abilities, but Psi Ops can self heal with soul fire and with enough control and stopping power you shouldnt even be taking hits

Sharpshooters: Rupture + pistol barrage fire = death

Psi Ops: They kind of lack stopping power by themselves. Their strong attacks are all on cooldown. Their damage and aim is ok, but only vs single targets, and no better than anything else. Of course, with 6 Psi Ops you could dominate 6 enemies and now it's 12 vs 7. Psi Ops excel in their crowd control and burst damage capabilities. If you use them right the enemy will never be allowed to take a shot at you again. Sadly they take forever to train, I'd start training them at the start of June and have 2 of them for the late game

Summary:

Psi Operatives are absurdly overpowered but require some skill and thoughtful play to use. They work extremely well with grenadier as they can CC anything the grenadiers fail to kill. Their dominate gives the team access to unique and overpowered enemy abilities like disable and shield, and the dominated enemies tend to draw fire when you can't finish the enemy. They can paralyse enemies for a turn which is best used on strong high HP enemies, and they have burst damage cooldowns and respectable damage, aim and range with their assault rifles. Begin production in May/early June to get 2 of them for the late game. Train them heavily for the stat increases, but you can bring them along early for some of their reliable moves like stasis and inspire

Rating:
8/10 - Below mystic level with stasis, sustain and dominate
9/10 - Above mystic level with stasis, sustain, dominate and some offensive spells
10/10 - Magus level with everything except fuse (just bring some grenadiers for AoE or sharpshooters with AP rounds for DPS)

So far I've seen 3 types of these guys:

Troopers:
These are the rank and file. They have terrible aim at 65, about 35% vs full cover at a long distance with no angle. 15% if you flashbang them, but as usual you really dont want to be taking more risks than necessary. You might have to let them take shots, but really you should be taking grenades over flashbangs to maximise your killing potential (with 1 flashbang for the event of an unfortunate sectoid mind control).

They are easily dispatched with grenades in veteran since they only have 3 hp, and assault rifles reliably OHKO them. However, in commander they have an extra hitpoint so at least half the time they survive grenades with 1HP. Shotgun, sniper, sword (with blademaster) and gatling gun hits still OHKO them though. You can also grenade and then finish them with a reliable attack like an elevated sniper rifle/pistol shot, specialist combat protocol, a close range shotgun shell (but beware of triggering new enemies and only do this as a last resort), or another grenade (which is wasteful unless you're desperate or you're on the last group)

If you poison these guys with a gas bomb it reduces their aim by 30%. If you flashbang it drops their aim by 20%. I got a specialist hack on a tower once which gave me a mind control on one of these guys, they can't hit the inside of a barn. He tried to point blank shot another trooper and it was a 65% hit chance, his exact aim. They're 10% more inaccurate than XCOM recruits and their "mag weapons" have similiar damage to your starting assault rifles. As such, poison and flash severely weakens their already bad aim, although you probably wont have gas til April/May even if you rush it. Be aware though that on Commander your guys typically go down in 2 hits, and even a 10% vs full cover will hit if they take enough shots. If you are all in full cover and 2 of these guys are poisoned, there's a 1% chance they'll both hit one of your guys, killing him, and a 10% chance that any hit will crit and kill your guy.

You really should eliminate these guys fast or sooner or later the RNG will screw you. These guys have an annoying tendency to rush in and flank you. They will only do this if a) there's a position that they can flank you in and b) that position won't leave them flanked by any of your own guys (that they can see, if someone is out of their line of sight and can see that position they will still make the flank)

Early on you dont have enough reliable abilities to bring them down as soon as you see them 100% guaranteed. As usual in the early game you should stick to the rooftops. If they cluster its worth 2 grenades to kill 2 of them, otherwise clear their cover with a grenade and finish with some elevated gunfire

Advanced troopers show up usually in May and replace the first troopers. They have 8 HP, +5 aim (about 35% to hit vs full cover), their mag rifles do 5 damage (7 crit) and they also get grenades that do 2-3 damage. The damage of their grenades is weak but can drop you through a roof or blow your cover, as well as put you in sickbay for weeks. You should be rolling out plasma grenades and improved grenade launchers around the time you see them. A plasma grenade will leave them at 1HP. Acid Bombs also leave them at 1HP, but they take 3 damage at the start of their turn and die. Hopefully you have scopes by this point and can finish them with gunfire, but you probably also have your third grenade on most of your grenadiers so you can probably afford to just volley them with grenades by this point

Elite troopers appear in July usually. They have 10HP (meaning acid bombs still OHKO them), another 5 aim, 10 defense (meaning you're 10% less likely to hit them) and most importantly they have 10% more crit meaning they now have a 20% chance to crit. They do 5-6 damage (7-8 crit) and they use normal frag grenades. Considering the level of your guys who should have scopes AND aim PCS with good armour theyre not that hard to hit and dont do that much damage for the point in the game you face them. Acid still OHKO them. If you have the time you can just plasma them and gun them down as they shouldnt be too hard to hit

Officers:
With 7 hp these guys can sometimes survive 2 grenades. They have 75 aim (that's 75% to hit at point blank, less at a distance against soldiers in cover) and do 3-4 damage (5-6 crit) with a 10% crit chance. This means they can OHKO a rookie if they roll a 4, and OHKO a spec/corp if they crit

They have a mark ability that increases aim, and possibly crit against the marked soldier by some unknown amount, and also causes all ADVENT troopers to focus fire on the marked soldier. This ability only costs a blue move, so they can fire after using it provided they didnt move. You should always make sure early on that if you cant kill the officer then he doesnt have a line of sight on any of your guys. If you do then he will move and use mark instead of firing. Like this you can focus on his troopers first and get another turn to deal with him when he wastes it on mark. When he dies the mark disappears. He can only mark one person at a time so pull a marked soldier back out of line of sight if you can't kill him, and if he marks someone else you can bring the soldier back forward again. Chances are if you give this guy a full turn to mark and fire he will kill a rookie, and will frequently crit your specs/corps out of full cover. They cannot use mark if they are flashbanged. They also carry standard frag grenades but I've never seen them use one

To kill an ADVENT officer blow away their cover then focus fire on them preferably with an elevation bonus. If you can finish with a sniper rifle thats great as sniper rifles minimum damage is 4. You can use a shotgun which can get 100% accuracy but you risk drawing more enemeis if you approach. Remember you can ignore him for a turn to kill his troopers providing he cant see anyone at the start of his turn, he will always move and mark someone but cannot fire because he had to move. He will shoot if he gets a flank though

Advanced officers appear in May and have 12 HP. They cannot be OHKO by an acid bomb. They now do 5-6 damage with their rifles (7-8 crit) and have a 15% chance to dodge, which halves the damage they take from the attack and makes it so it wont crit. They cant dodge grenades so either hit them with 2 plasmas, or hit them with an acid and then shoot them for at least 2 damage so the acid kills them on their turn

Elite officers appear in July with 15 HP. 2 Plasma grenades won't kill them anymore. An acid and a plasma grenade will (they survive at 1 HP but die on their turn from the acid). They do 7-damage with their rifles now, (9-10 crit) and do 3-6 damage with grenades with 3 shred. They also get +10 defense and +5 aim. I've heard these guys use grenades a lot but I never gave them the chance. Their damage is actually quite dangerous now and they have their usual mark ability. Consider using stasis, dominate, or fire on them if you cant kill them your turn. Since you really should have scopes and aim PCS by this point and plasma weapons will kill them fast you could just destroy their cover and gun them down, which even with grenadiers should be fairly accurate by this point, and 100% accurate with your Psi Ops

ADVENT Lancers:

Stun lancers first appear in late March. You won't have much time before they appear. They do 3-4 damage with their rifles, 2-4 with their lancers which have a chance to stun based on soldier willpower, meaning they tend to stun a lot early on. They have 7HP, 65 aim, and 15% crit. Their notably high crit and unpredictability, along with their lances which tend to knockout soldiers hit by them makes them extremely deadly. They can use their lances on a dash. As with officers, 2 grenades might not kill them. They sometimes come in pairs in April, accompanying snake ladies, and can stun soldiers who have been bound by a snake.

Heavy lancers appear in July with 8HP, 1 armour, only 4-5 rifle damage, 5-7 lance damage, 20% crit, 10% defense and 25% dodge. They still die fast but their increased dodge makes shooting them unreliable, and their high crit makes them deadly. They probably wont knock out mid level soldiers but their sheer damage makes them dangerous. Acid bombs will OHKO them as they take acid damage at the start of their turn. Highly recommend you kill them with explosives, or use a plasma grenade and shoot them as a grazed shot will still finish them. Due to their insane crit you really cannot give these guys a chance to attack

Elite lancers appear in August and have 12 HP, 5-6 rifle damage, 8-10 lance damage, no armour and only 20% dodge. They can be killed in 2 plasma grenades, or an acid grenade and a single shot to ensure the acid damage kills them. As usual their crit is insane and their lances do a ton of damage, dont let them attack

All versions of lancers have their melee attack disabled by flashbangs/fire, but with their crit chance you dont want them shooting at you either, just kill them quickly if you can. Overwatch is very unreliable, because it suffers an aim penalty of -15, plus a further unknown aim penalty against dashing enemies, so it's like shooting at them in full cover

ADVENT Shieldbearers:

Shieldbearers appear in May and have 8 HP and 2 armour. They have 70 aim and do 5-6 damage with their rifles and have a 10% crit chance, similiar to the officers but with a bit less aim. They have a shield ability they can use only once that gives all enemies in close proximity to them a 3 health shield. The shield will be dispelled if the shieldbearer dies.

Elite shieldbearers appear in July and have 9 HP, 3 armour, and 75 aim. Their shield ability now shields for 5 damage.

They tend to accompany snakemen, officers and MECs. They always use their shield ability on the first turn then start shooting, but tend to stay at a distance in full cover.

You may think you should prioritise killing these guys first but that is not so. They will always use their first turn to cast a shield, which means if you kill all their friends first then they only end up shielding themselves, essentially wasting their turn as you can focus fire on them with your entire squad next turn. Even in their elite form their HP is awful. An acid grenade will OHKO as it bypasses armour, it will also shred their armour but theres no need to finish them as the acid damage will do that. These guys are only a threat if you activate them at the very end of your turn somehow, allowing them to shield their entire group, but if you did that then it means the enemy are going to get free shots which is even worse. If you somehow do blunder so badly that you activate the group at the end of your turn, try to kill his allies with your remaining turns, then at the start of your next turn kill him to drop the shields and then finish his allies. Remember that you can afford to let these guys live a turn as they will never fire at you on their first turn, they should be at the bottom of your kill priority

Sectoids:

Sectoids are one of the starting enemies. They have 8 HP, 75 aim, 10% crit and their plasma blasters do 3-4 damage. They take double damage from melee, but you risk pulling new enemies by rushing in unless you're dealing with the last group, and even then you might draw line of sight with a turret

These guys can be brutal early on. If you leave them alive it's really anyone's guess what they will do. They can use psi-panic, psi-disorient, psi-zombie and mindspin. Disorient is like a flashbang on one guy, which means no special abilities, items, or reload, plus -20% aim. Panic could cause your soldier to do any of a number of things, such as taking a free low accuracy shot, hunkering down, moving to new cover (which could leave him flanked or in better or worse cover), hunker down (ideal) or use an items (if its a grenade this can be terrible!). I've heard panicked soldiers can still shoot each other but I've never seen it, so it seems to be rare. Psi-zombie raises a weak zombie that will disappear if the sectoid dies. Mindspin can apply disorient or panic, but there's a fairly high chance it will apply mind control for 2 turns. Mind affected soldiers could remain affect for up to 2 turns, and panicked soldiers cannot be used. Killing the sectoid will sometimes remove panic. Killing the sectoid will always remove mind control, as will flashbanging it. Beware as flashbanged sectoids cannot use their abilities they'll start shooting with their plasma blasters instead which is usually more dangerous than their psi attacks

I would usually leave these guys low in my target priority since more often than not they waste a turn on a zombie, they rarely shoot, and provided you have a flashbang you can break mind control if the sectoid took an awful position. Beware though, sometimes sectoids get a free move with your mind controlled guy, though I've only see it happen twice. Their insanity ability works less often on high will soldiers, which means they rarely succeed with insanity when your soldiers reach mid levels. It's worth using any will PCS you get early to help with these guys, and replace it with aim later. I suggest you let them live a turn, then blow their cover with a grenade and focus fire. If you're sure you won't pull new enemies you can OHKO them with a blademaster ranger, as the minimum damage they can do is 4 with blademaster, and they get double damage on sectoids

In May they start to appear in place of troopers, or in packs of 3. You should eliminate them quickly when they appear in groups or you run the risk of most of your team being affected by panic or mind control. Around this time you'll be getting plasma grenades so AoE them. An acid bomb will OHKO them, it's worth using a fire bomb or flashbang if you have predator armour as their wrist plasma won't do much damage by May considering how much HP you have. They can be used to create mind shields to protect against psi attacks, but taking mind shields instead of grenades not only cripples your finances but also your offensive capabilities. Flashbangs are a cheaper and more effective way of dealing with them

Zombies

These guys are raised by sectoids and can move the next turn. They don't use cover and have about 6HP so can be easily dispatched in a couple of hits, one if you get a lucky shot.

They die if you kill the sectoid who raised them, but sectoids often raise these guys from behind full or indestructable cover. Consider shooting the zombie then taking shots at the sectoid, rather then advancing and risking new contact.

Zombies don't hit very hard, but they have about an 80% hit rate. Unlock shock troopers they can't hit on a dash, and have slightly less movement range than your men, so if you blue move directly away they will follow but wont be able to attack. They only do 3 damage but you should still kill them if you arent sure you can finish the sectoid, unless you're running out of time. As a last resort you can rush a ranger in to dispatch the sectoid and thus eliminate the zombie, just be careful of pulling new contact while still dealing with enemies or without a full move to deal with them (especially since, if you dashed your ranger to melee, that means the rest of your team is a whole dash away from the new enemies)

Snake:

Snakemen appear in April. They have 8Hp, 70 aim, 10% crit and a 1/3 chance to dodge. Their plasma rifles do 3-5 damage and they can use a blue move to launch a gas cloud then fire immediately after. Soldiers caught in the gas suffer poison which reduces your movement, your aim by 30, and causes them to suffer periodic damage until cured with a medkit. Even when healed they will count as wounded at the end of the mission so you want to avoid this. They have a bind attack they can use on troops in blue move range, and a tongue grab attack they use on a blue move to pull soldiers in. Because tongue grab and poison use only a blue move they fire after, unless the tongue grab was successful in which case they bind. Some enemies like andromedon will melee bound soldiers, injuring the snake as well.

As you face them so early you really do not want them shooting at you, they can OHKO corporals with a 5 damage shot, and a crit will OHKO mid level soldiers as well. If you cannot kill the snakeman on your turn then consider dashing someone into melee range so it binds them for 2-3 damage instead. They will continue to constrict for 2-3 damage a turn and do nothing else in the meantime, allowing you to dispatch them at your leisure. Just beware as usual that rushing in or being pulled in might cause you to take contact.

They're really awkward to deal with in April since, as with sectoids they take a ton of damage, but unlike sectoids they often use their abilities and fire in the same turn and do more damage. You probably dont have Captain grenadiers yet, let alone plasma/acid so you cant really bring enough damage down on them reliably, especially with their high dodge. If you cant kill them and cant risk rushing a soldier in close then you should try to break line of sight and spread your soldiers. This will usually result in them closing in and using their tongue grab. This means they will have used their blue move to close in and their yellow move to tongue grab so they wont get to fire if it misses, and since they closed in you can rush in to flank/melee without drawing new contact. By May you should have better grenades and can take them down with AoE damage and follow up shots on the exposed enemy. Acid bombs OHKO them with a captain grenadier. You can break their bind attack, or disable their bind and poison abilities with a flashbang, but this wont stop them shooting with only a -20 aim penalty which can be much more dangerous

The tend to appear alongside stun lancers early on, and the lancers definetly take priority so you need to consider what they are going to do on their turn. If they're in an open area closing in will almost certainly pull contact, but its dangerous to let them fire or spew acid, and they might just pull a guy in anyway and cause him to trigger new enemies. When you plan your battle with them you should first find out which positions allow your soldiers to see the lancers without being seen by the snake. Your position is MUCH more secure if you can force the snake to move before it can attack, while also dealing with it's lancers. They accompany stronger enemies in July as support units and should be AoEd down with plasma/acid grenades

MEC:

MECs appear at the start of April usually. They have 8 HP and 2 armour. They have 75 aim, their guns do 4-6 damage (7-8 crit) with 1 shred, and their missile barrage does 3 damage with 1 shred.

MECs count as cyborg enemies and have a tendency to rush your men and use a missile volley, then rush in for point blank gun shots on their second turns.

It is VERY important that if a MEC is active you get everyone off the rooftops ASAP unless you can kill the MEC. If you don't then they will grenade your guys, causing minor damage, and then your soldier will fall for up to 5 more damage. Be careful to keep a good spread on your soldiers, they will grenade on their turn and destroy cover so prioritise indestructable cover like ridges, or strong cover like trees or UFO walls. So long as no one else is active on their turn the grenade damage is negligible and no one can take advantage of your coverless wounded soldier

Specialists combat protocol does 4 damage and ignores armour, as usual this always hits so you can finish with that early. Grenadier shredder ammo (corporal) will not only do high damage but remove armour, although you will want blast armour on your grenadiers early on and grenades shred 1 armour, plasma grenades 2. They tend to stand in the open and their HP isnt exactly staggering, so you can grenade them for 1 point of armour shred, then just shoot them or finish a 4 or less HP one with combat protocol which ignores armour. You can use haywire protocol if you dont mind passing up on revival in case you get unlucky with lancers, this will stun the MEC for 2 turns but only if the hack succeeds

As for priority, I'd kill them first if you want to keep your height advantage, or kill them last if you're on the ground as their missile volley doesnt hit very hard, although it will send someone to sickbay. If they're with sectoids or troopers and your men are sergeant+ rank then you can focus the MEC down first as the troopers/sectoids are unlikely to kill anyone and might miss, allowing you to dodge the sickbay. Do NOT let them have a second turn, at the point in the game that you face them their guns WILL kill you.

By late April you will likely have transitioned to a 4 grenadiers, 1 ranger squad. There's no need to grenade them twice, as one grenade will take a point off their armour, then 1-2 cannons shots will finish them. Even those grenadier aim sucks they tend to stand in the open fairly close so it shouldnt be too hard to finish them. You can get on a roof for the aim bonus but ONLY if you can finish the MEC or you WILL die

Elite MECs appear in June. They are distinctly red, and have 15 HP, 3 armour, 10 defense and 80 aim. Their guns do 8-9 damage with 2 shred, and their missiles do 3-5 damage with 1 shred. Same rules apply as with normal MECs. You can wipe their armour and do 7 (+3 on their turn) damage with an acid grenade, then they only need 1 shot to ensure they will die. Since you've got about 3 months before these guys start to appear you really have no excuse if you dont have Lieutenant/Captain grenadiers, squad size 2 for 5 of them with plasma grenades and scopes, and a few aim PCS from the black market. Beware as these guys go on overwatch the same turn they spot you, even if it's still your turn. If you need to move a grenadier up to get a grenade on them then be very careful not to move more than 1 tile into their sight range as their guns will hit like a train and you probably only have predator armour at this point

Turrets:

Turrets appear in March and have only 50 aim, 3-4 damage and cannot crit. They have only 5 HP but they have 3 armour. Sometimes they don't do anything on their turn. You can ignore these guys for a turn to focus on any active enemies but don't go thinking they are worthless. You could still take 2 unlucky hits, they can OHKO a rookie or two-shot a spec/corp. You can easily kill them if you do 1 damage by any means and finish with a combat protocol specialist. Cannons and sniper rifles have a minimum damage of 4 so will do at least 1 damage and allow the specialist to finish. As they cannot move you are safe from them so long as you break line of sight, but if you need to reposition to face new enemies or you advance past them and trigger enemies in front you could be caught in a crossfire so unless you are desperately short on time it's worth taking the time to deal with them. I wouldnt recommend grenades as they will likely do 0 damage, 1 if you're lucky, and shred only 1 point of armour. If you dont have combat protocol you can throw 1 or 2 grenades and finish with some shots but it really is wasteful. If you have a grenadier with shredder you can take of 2 points of armour and do 1-3 damage, then finish with 1 more shot, but you really need blast armour on your grenadiers early on

There are armour piercing (ignore armour) methods of combat but early on you only really have access to combat protocol for this.

Heavy turrets appear in May and have have 6 HP, 4 armour, 60 aim and 10% crit. They do 5-6 damage (7-8 crit). Their aim is still terrible, and the +1 armour isnt a huge deal as you start to bring mag/gauss weapons out. Their increased damage and crit is negligible as your soldiers are higher level with more HP, and should soon be getting the 4HP from predator armour as well. You should also be getting plasma grenades and improved explosives around this time, and getting special grenades in June so heavy turrets arent such a huge deal at this time. The only real problem for me is that I tend to get the AWC in July which means I don't have shredder ammo at this time. A single plasma grenade fired by a captain grenadier will do 3 damage and shave off 2 armour, and a gauss cannon/sniper or shard gun shot will finish the job. If you have bluescreen or AP ammo equipped in the second predator armour slot you can OHKO them if you hit due to their low HP

Super turrets appear in July. They have 12 HP, 5 armour, same damage as heavy turrets, and 65 aim. They're not much better than stationary starting troopers but with their high armour and mid-low HP can be a pain to kill. By this time I usually have switched all my grenadiers to shredder ammo and with plasma cannons, scopes and aim PCS it's no problem to just shoot them a couple of times. As I have Psi Ops as well by this time I often hit them with a cannon shot to shred 3 armour and soften them up, then finish with a plasma rifle shot if I don't need any Psi abilities. Psi attacks hit through armour so a lucky high damage null lance can OHKO one, and soul fire will finish a damage turret

Faceless:

Faceless appear in retaliation missions disguised as civilians. They have 10Hp, 75 aim, and an AoE swipe that does 3-4 damage with a 15% crit chance. It also smashes the floor, causing the victim to take additional falling damage. Until you get predator armour and mid level soldiers they are very dangerous, but their damage becomes negligible against troops on the ground at higher levels.

Any civilian could be a faceless. They will transform when you try to rescue them, but will also transform if you end your turn within a blue move of them and can attack the same turn they reveal themselves. You should try to estimate whether you are within a blue move of a civilian and avoid ending your turn too close unless you have already scanned them

Battle scanners and the specialist scanning protocol will reveal civilians who are actually faceless. For the May and April retaliation mission you should bring a couple of battle scanners and use them on any civilians in your path or that will be within a blue move distance of you as you advance. Faceless are very bullet spongey, and you cant afford to waste much time on retaliation missions so just rush the enemies, only scan civilians in your path, and dont waste time trying to save civilians.

In May and beyond you probably already have predator armour and mid level soldiers, so these guys cant seriously injure you anymore, just focus on rushing for the enemies using a stealth ranger to scout ahead, and deal with the faceless as and when they appear, just try not to stand too close together so you dont all end up in the sickbay. Retaliation missions suck either way and its better for a couple of people to be out of action for a week than risk losing the mission due to civilian death, and faceless just don't scale up with your team

Muton:

Mutons usually appear in late April. They have 9 HP, 2 armour, 80 aim, 10 defense, 10 crit, and do 4-6 damage (7-8 crit) with their plasma rifles. They carry single use plasma grenades that do 4-5 damage (1 shred) over a large area and destroy cover. They also have a melee attack that hits for 6-8 damage and can stun, and can execute stunned soldiers. Their are no elite mutons, but they can appear in groups starting in June and do massive AoE damage and cover destruction with their grenades. They have an unknown chance to instantly kill rangers who try to melee them

The main danger of mutons is their grenades. It really does have a massive AoE range, and 3 plasma grenades does 12-15 damage with cover destruction and cannot miss, but you cant afford to spread your troops since you need them all together to deal with contact with focused fire and minimise your chances of activating more enemies, there's nothing worse than having a group of enemies appear on your flank and having half your squad too far to assist in bringing them down

Mutons have comparible survivability to MECs, but they also use cover and their AoE is far more lethal. I highly recommend you make them your priority to eliminate, even in the late game their AoE and cover destruction is no joke. You'll still be using frag grenades when you face them and have limited single target dps. It's not overkill to hit these guys with 2 grenades and focus fire, I'd even bring my ranger out of stealth and rush them up close to finish them, pulling another group of enemies at the end of my turn is preferable to leaving one of these guys alive

When you have acid bombs and a captain grenadier you can kill mutons in one shot thanks to the additional 3 damage they take at the start of their turn. A sharpshooter armed with AP rounds or dragon rounds can kill them in 2 pistol shots. In the late game you can stasis them with a Psi Op, its definetly not a waste

You should autopsy a muton ASAP for the improved grenade launcher, plasma grenades and enhanced explosives which make the mid-game much easier

Berserker:

Berserkers appear in May. They have 24 HP, high movement, 75 aim, 15% crit, and does 6-7 damage (7-8 crit) with it's melee attacks. They have a melee cooldown that does 5-8 damage (9-10 crit) and has a high chance to stun. When injured they enrage, increasing their mobility but causes them to sometimes target other enemies instead of XCOM. Like lancers, they can attack on a dash. You could face multiple berserkers in a group starting in August, but your Psi Ops and Grenadiers should be well developed enough to handle them, and by this time you probably have colonel sharpshooters with dragon/bluescreen rounds as well

Berserkers are the first bullet sponge enemy you face, they cannot be taken down with a couple of grenades, and unless you have Captain sharpshooters with dragon rounds you will probably have to spend an entire turn focus firing them to kill them. I recommend you attempt to AoE them with grenades to eliminate their allies, then focus fire and try to finish the berserker. If you have to choose between killing the berserker or its allies, then kill its allies if your soldiers are exposed (such as if you moved some into the open to take point blank shots) or kill the berserker if your soldiers are in cover. Though you should still prioritise killing mutons over the berserker. Chances are the berserker wont insta kill a mid level soldier in predator armour but even if they survive they will be KO. You should be able to kill them and their allies in one turn if you autopsied a muton as soon as you could and got all the grenade upgrades, especially if you got an acid bomb from experimental grenades

Due to how hard sharpshooters are to train, and how much of a deadweight they are until you do, I wouldnt recommend training them up just for this and praying on dragon rounds when you produce experimental ammo. If you have mid level Psi Ops in June consider bringing one just to stasis these guys to buy more time to finish them. They're a pain on terror missions where you have to rush, especially if a faceless injures one of your men, meaning the berserker can one hit kill them potentially

And now we get into the late game bullet sponge enemies. I might as well say this here to save time, you need either high level sharpshooters with bluescreen/dragon rounds or mid-high level psi ops with stasis (and sustain to be safe) to be sure these guys wont get a shot against you. They really are very dangerous and their high damage soaking and armour means that your muton enhanced grenades just wont cut it reliably anymore

Archon:

Archons appear in Mid-June. They have 20 HP (4 less than berserkers) but also have 25 defence, 25 dodge, 75 aim, 10 crit and high mobility. Their plasma lance shot hits for 7-8 damage, and they have a melee sweep that can hit multiple targets for 6-9 damage. In August they start appearing alongside Andromedons or in packs, so you really must have Psi Ops or dragon round sharpshooters by this point, or hope they cluster

When wounded they have a chance to go into a battle frenzy, giving them an additional action point for movement which allows them to easily flank. As they dont use cover they will simply rush around you and fire from out in the open.

They also have an attack called Blazing Pinions where they hover high in the air and mark the ground with red markers, which explode next turn. They cannot attack on the same turn they cast this ability, but can attack on the same turn that the markers explode. I have no idea how much damage this does as I never stayed in the markers.

Due to their high mobility with battle frenzy and moderate damage they can be extremely dangerous when left alive. Their aim is quite good, and with their high dodge, HP and defence they are very difficult to eliminate. If you dont have a psi op to cast stasis, or a sharpshooter with dragon rounds to burn them down fast, then you need 2 captain grenadiers. A plasma grenade will hit for 7 damage, and an acid grenade will hit for 7 damage plus 3 on their turn. You only need to cause 3 more damage by any source to ensure they die at the start of their turn, and even a graze shot from a mag cannon will do at least 3 damage. If you cannot finish them with gunfire then use a third grenade to finish them, it takes 3 plasma grenades to kill them if you dont have acid. Even with their high defence, a well trained sharpshooter can finish them with multiple dragon round pistol shots with near 100% accuracy at a distance provided they have good scopes and aim PCS

Andromedon:

Andromedon appear in mid July, usually after I produce Warden armour. They have 18HP and 4 armour, 80 aim, 10% crit and 10 defense. Their cannons do 9-11 damage (12-14 crit!) with 2 shred. They have a melee attack that does 7-10 damage but with only 65 aim (60 for shell) and can hit multiple targets and damage cover. They also have an acid bomb cooldown that functions similiarly to your own acid bombs, doing 5-7 damage with an additional 3 damage at the start of your turns, with a fairly large AoE and 3 shred. As they move they leave a trail of acid that can afflict the acid DoT on anyone who steps on it. Any objects or cover they touch as they move will be destroyed. Andromedon count as organic, meaning they are affected by dominate, poison and dragon rounds

When killed they become Andromedon Shell which has another 12 HP, no armour, and can only use its fist attack with only 60 aim. Like faceless, they cannot attack on a dash. Andromedon shell can be hacked, can be affected by EMPs and bluescreen rounds, and if a dominated andromedon dies and becomes a shell it turns hostile to you.

Andromedon are extremely dangerous. They have less HP than archons or berserkers but more armour. They technically have more HP if you count their shells. As they have less defense and HP than archons they can be killed quite quickly with AP rounds on a sharpshooter or with psi magic. A single acid grenade will destroy all their armour and cleave half their health. As their shells are much less dangerous it is highly recommended you destroy their first form immediately. You can ignore their second form provided it isnt within a blue move of you. A dominated Andromedon is extremely useful as it can be used to draw fire, and it's acid grenade cooldown is very effective

You really should have mid level Psi Ops by this point, I suggest you kill the andromedon's allies, then do as much damage as you can before casting stasis so you can finish it next turn. When you get plasma weapons they can be killed quite easily so they only remain a problem for a month really

The super enemies of the game, tougher than archons and andromedons with far greater destructive power. However by this time you will likely have psi operatives, colonel sharpshooters, experimental ammo and plasma grade weapons. With all the methods of burst damage and control available by this time they're not hard to handle

Sectopod:

These appear in late-July, early-August. They have 32 HP and 5 armour, 70 aim, 10% crit and high mobility. Their laser does 10-11 damage (12-14 crit)

Like quickdraw gunslingers, the sectopod's laser only using 1 action, this means they can potentially fire it twice in a single turn. They can raise or lower, allowing them to see targets on a higher floor, or to gain a +20 aim height advantage on targets lower than them, this does not cost them an action. They can jump onto buildings also. They have a charged beam attack that hits everyone in a cone. To use it they must activate it at the end of their turn, and it will fire at the start of their next turn. This does not cost them any actions, so they can fire twice, charge their cannon, then at the start of their next turn fire the cannon, fire twice, then charge it again!

They also have an AoE lightning attack on a cooldown that hits everyone in melee range for 7-9 damage and costs 1 action. When they die they explode for 7 damage in a 3 tile radius, and destroy objects as they move through them, and can destroy mission objectives or evac points in this way

The sheer destructive power of sectopods is staggering, and combined with their high health and armour you really should not engage one of these without a colonel specialist with a skullmine and improved gremlin, or a psi op. Due to their high tech level its difficult to even shut one down with a specialist, but psi ops stasis is much more reliable. They can be hack controlled for 2 turns but its hard to pull off and too much of a gamble. I have heard EMPs shut them down frequently but I have never tested it. Bluescreen rounds do 5 damage and bypass armour. A single sharpshooter can do 60 damage with lightning hands, quickdraw and fan fire vs a ruptured sectopod using bluescreen ammo and a beam pistol assuming they hit every shot, do minimum damage and don't crit. Therefore a Psi Op + colonel sharpshooter combo can deal with the problem in one turn

I suggest you use AoE damage to break their armour, kill their allies and soften them, then take cannon shots/psi spells on the sectopod, then stasis it if its still alive and your last psi op cant finish it, then finish it off next turn

Gatekeeper:

Gatekeepers appear in August. They have 25 HP, 6 armour, 40 defense, 80 aim and 10% crit. They do 9-12 damage with their beam cannon (13-15 crit!!) and frequently fire with a +20 aim bonus from elevation

Gatekeepers are also psionic enemies who have 3 psionic attacks. Consume is a melee range psionic attack that causes psionic damage and heal the gatekeeper, like the psi ops soul steal ability. They can also mind control, which unlike the sectoid version is much more reliable and frequently used, and cannot be broken with flashbangs. They also have a mass psi zombie summon, and while psi zombies arent that dangerous at this stage they can still cause a lot of harm with multiple attacks. Like sectopods they explode when they die, and destroy objects and cover as they move through them.

I've personally never let them get an attack, since by this point I always have plasma weapons and magus level psi operatives. If you cant kill them then stasis or dominate them. Gatekeepers cannot be hacked. They take extra damage from bluescreen rounds, but after attacking they are briefly open where they have lower defense and armour, and in their open state dragon rounds affect them. If they take damage while open they close, so if you want to attack with a sharpshooter who has dragon rounds consider not using quickdraw or lightning hands and hitting them with fanfire instead which will likely OHKO them

Chrysalid:

Chrysalids appear in June on retaliation and certain story missions. They have only 10 HP, 1 armour but 20 dodge and 10 defense. They have 75 aim and 15% crit. Their melee attack does 5-6 damage and inflicts chrysalid poison.

Statistically chrysalids are pathetic, but their abilities make them a nuisance. Chrysalid poison doesnt wear off unless you evac or use a medpac and the damage is fairly high. Anyone who dies from chrysalid poison turns into 3 more chrysalids. Chrysalids can also burrow, making them invisible, and if you step within blue move range they can emerge and attack even during your turn. Whereas faceless take the form of humans, giving you a clear target to scan, chrysalids leave no visible indicator of their presence meaning you have to toss battlescanners all over the place.

A blademaster's bladestorm ability can kill a wounded chrysalid but is unlikely to finish one at full health, although the fire damage of fusion blade will finish it when your turn ends. Carrying a couple of nanomedkits on a retaliation mission can allow you to heal and cure the poison from a chrysalid ambush, but will still leave the soldier in sickbay. Chrysalids are pretty easily to kill once exposed due to their low HP. A single acid bomb can eliminate a pack of 3 chrysalids when fired by a Captain grenadier. Sometimes dark events can cause chrysalids to appear in other missions, which can be horrifying if they appear on a VIP escort mission as they can emerge and kill the VIP while it's still your turn!

Honestly I feel these things are more of a pest than anything dangerous. Just bring a couple of nanomedkits on retaliation missions and toss battle scanners ahead of you as you proceed. If you get a flea bite then step on it and heal

Codex:

These are such a massive nuisance to deal with. They appear after you use skulljack on an officer for the first time (one appears the first time you do it but not subsequent times) and spawn in pairs on subsequent missions, usually accompanying something else like an andromedon.

They have 12 HP, no armour, do 5-6 damage with their rifles, and their other stats are currently unknown. Their high will makes them difficult to dominate

When injured the codex will clone, halving its HP, teleport, and leave another codex with the same abilities that cannot clone. The clone will have all its abilities off cooldown though it cannot clone, and if you kill the main codex its cloning ability will jump to its clone. They usually cast psionic rift on their first turn, which doesnt do damage until the next alien turn but empties your weapon clips. This does not disable secondary weapons like pistols, swords, grenade launchers, psi or gremlin drones. You should move out of this and reload to avoid taking damage, the free reload weapon enhancement is extremely helpful for dealing with them. By late game their weapons arent really all that dangerous, especially if you have 1 or 2 armour points. They're really only dangerous when accompanied by other enemies.

If you flashbang a codex it cannot clone. This is very important as due to their high dodge you cannot reliably OHKO them even in late game without a sharpshooter's damage cooldowns, and being able to just blow their cover and wound them with a grenade then finish with a shot makes them much easier to handle. In the late game it's worth trying to dominate one with a psi op. Their disable ability, when combined with fire which disables abilities and reloading, allows you to totally cripple an entire group of enemies, or at least give you another turn as they will move out of the rift and reload. Dominated codex will not clone

I need confirmation on whether these enemies are affected by blue screen or dragon rounds, or EMP grenades and whether EMPs shut down their cloning ability.

"Special Enemy" - What a horrible nuisance these guys are. It's not so bad the first time since it's health is only 2/3 but you fight 3 of them in the final fight with full health and in a situation where you're caught in a constant crossfire and where your grenades often bug so you can only fire them 4 feet away making it really hard to catch these teleporting troll dolls

They have 30 health, 3 armour, 25% dodge and 15 defense. They have 85 aim, 20% crit, and do 11-13 damage with their rifles (I've seen a 16 crit)

Usually these use mind control as their first move. As they have extreme psionic power there's basically no chance of resisting it. Fortunately a psi operative's Solace passive will dispel mind control from nearby allies, and this enemy oftens mind controls people who are next to psi operatives causing it to be immediately dispelled. If you don't have a psi operative with solace then this will be hell

Sometimes they use psionic rift instead. This is a massive AoE psionic attack that bypasses armour for 7-10 damage on everyone hit, and explodes for 7-10 more damage on anyone still inside when it ends. This not only does a lot of damage but forces everyone to move, often on a dash to get out of it. It can scatter your team, and disrupt any plans to reload and hail of bullets the enemy. This rift explodes at the start of your next turn so don't make the mistakes of thinking that if the enemy teleports into it then it will be harmed by its own rift, it will simply move out on it's turn

Their final ability is null lance. This is the same as your own psi operatives null lance but I've never seen them use it before. I'm guessing it has low priority so you really should kill it before it gets around to using this move

They teleport after every hit and regenerate 5 HP at the start of their turn. This makes the usual cover destruction and focus fire tactic impractical as they will teleport when the grenade hits. You should eliminate any dangerous enemies first, then focus fire on them with reliably attacks. That means grenades, hail of bullets, capacitor discharge, combat protocol, elevated sharpshooter fire, run and gun shotguns, null lance, void rift or mind controlled enemy attacks like an andromedon acid bomb or a muton grenade

The first one that appears when you skulljack a codex isn't too tough as he is alone and injured. I suggest you complete the objective and clear all other enemies, then stasis the codex so you can skulljack it on a fresh turn. You should then be able to kill this enemy the same turn it appears with hail of bullets, grenades and null lances. It's not a bad idea to trigger this enemy on a blacksite or a story mission so you don't have to deal with a timer

Since the final mission ends when you finish these guys you may feel like you should focus fire on them and kill them fast, but you can get quickly overrun if you do that, and due to these guys tendency to teleport you will have to scatter a lot to keep fire on them which allows the remaining enemies to easily flank your men. I recommend you stay near the center of the room around the elevated platform, eliminate dangerous enemies like mutons and MECs first, preferably with AoE, then focus fire on the special enemy but don't let yourself get too scattered. When he mind controls on his turn you should be able to disrupt it with solace and be safe to scatter a bit and focus fire before pulling back next turn to the platform to wait for the next wave of enemies.

By the end-game their 5HP regen is really no big deal, and your psi-lance and hail of bullets have a fairly long cooldown so you really need to keep on top of the waves of enemies and focus fire on these guys only when its safe to do so, so that you don't get overrun. You should ideally kill them the turn after they use mind control though to reduce the risk of taking a psi void rift which can really ruin everything

Enemies appear in groups (pods) of 3, this section is for strategies for countering each group type, including when you are likely to see them and what the best ways to not only fight them but to prepare for when you are going to fight them are.

March:

April:

1 Snake, 1 Lancer, 1 Trooper - If you cannot eliminate them all in one turn, prioritise the trooper and the snake. You can flashbang the snake to stop it using poison or tongue pull but it will hurt if it hits. If this is the last group on the map you can send someone into melee range of the snake so it wastes a turn on a low damage contrict, but this will leave the character in the sickbay potentially for weeks. If you cannot advance then try to kill the lancer and snake first, the trooper will likely run away to join another group, or take a shot which is unlikely to kill sergeants or anyone in predator armour. Whatever you do, don't leave the snake free to use acid, or the lancer free to use a melee attack. It would be better to use your flashbang than let it put multiple people in sickbay and force you to evac them

May:

June:

July:

August:

Special:

Grenades:

Grenade -

Plasma Grenade -

Flashbang -

Smoke -

Acid -

Fire -

Gas -

Blue Screen -

Proximity Mine -

Ammo:

Viper -

Tracer -

Blue Screen -

Armour boosts:

Hellfire -

Special Armours:

EXO/WAR -

Spider -

Wraith -

Heavy Weapons:

Shredder -

Plasma cannon -

Rocket -

Flamethrower -

Other:

Decoy -

Battle Scanner -

Medkit/Nanomedkit -

Skullmine -

Cover:

This is helpful not reliable. Due to the random nature of the game you should proceed under the assumption that any enemy who can see you will hit you on their turn, and take cover only for the chance that they won't. Always take full cover, but if you have a choice of going into half cover for a high chance to eliminate the enemy, and thus prevent return fire then you really should. It's always better to eliminate the enemy fast than to take a strong defensive position and risk taking fire. However, even when going for the kill you shouldn't move your guys out of cover unless the situation is desperate, if you accidentally activate more enemies or miss a 95% shot then not only are attacks guaranteed to hit your exposed man, but they have a 40% to crit, killing him instantly

Aggression:

As I say, you really need to wipe the enemy force on your first turn, second at the most. The more shots your enemy gets to take the more likely someone will be hit, and the more likely they'll take 2 unlucky hits and die. Engage enemy pods as soon as you see them, even if it means breaking concealment in your second turn, only delaying the fight to position your troops in advance, to let the enemy get closer, and to give yourself a fresh turn to engage

Reliable tactics:

Point blank assault rifle/gatling gun shots are not reliable. Grenades on a 4HP enemy are not reliable. Overwatch is REALLY not reliable.

Elevated sniper shots/pistol shots with a scope on an exposed enemy are frequently 100%, that is reliable. Grenades for cover blowing or finishing <4 HP enemies are reliable. Combat protocol against <3HP enemies or <5 HP MECs are reliable. Point blank shotgun blasts are reliable. You may feel angry when you miss an 85% point blank assault rifle shot and one of your men dies, but if you're counting on an 85% shot to hit then the situation is already desperate.

Generally speaking you should scout with your ranger who can potentially dash and slash, and always move your scout into a covered position. If you're concealed then you should kick the fight off with an elevated sniper shot, preferably on the highest HP enemy unless it's a MEC (since they'll stay in the open anyway). You should then use grenades to blow cover, and use close range shotgun shells and specialist combat protocol to finish wounded enemies. Soldiers who can't get a 100% shot or use a guaranteed damage ability should finish the stragglers with grenades if necessary. If you can't finish the enemy in your turn then you need to consider what the enemy will do in their turn

Enemy tactics:

The enemy will usually take full cover and then concentrate fire on one member of your squad. this is dire if the enemy still has a commander up. If you can't kill the commander then you must kill every other enemy. If there's someone you can't reliably kill then you must kill the commander. If you cannot kill the commander or his comrades then you're in desperate trouble, you must dash your men away so they cannot pursue and fire in 1 turn. If you've already made moves and so cannot dash away then you either didn't consider whether you could kill the commander or all of his henchmen, or you misunderstood something such as attempting to destroy indestructable cover with a grenade, or blowing out a wall and getting line of sight on new enemies and then being forced to deal with them.

If you only have one enemy left then it can still be dangerous if it gets a flank due to the high crit chances. Flashbangs are really unreliable, if you cannot kill everyone but you know you can kill all but one enemy then it's important to understand enemy flanking tactics. The enemy will only flank you if he can reach a flanking position and if the flanking won't leave him flanked. For instance, if you have an exposed 1 HP trooper and you can move a specialist up to take an 85% shot from full cover, it's not safe if there's a position he can flank you from if you miss, unless the position he can flank you from is being watched by one of your own troops. Be aware that the position MUST be visible to your soldier, it's no good if they can easily flank the enemy soldier if he moves there, they must already be flanking that cover or he will take the flank and kill your guy. If there's no position he can flank your guy from that isnt being flanked by one of your own soldiers then the enemy will either pull back or overwatch

Be aware that even if you have a soldier flanking a position where the enemy could flank your guy, if the enemy doesn't know that then he will take the flank anyway.

In terror missions the enemy is programmed to kill one civilian per turn. If there's only one enemy left on the map and there's a civilian nearby he'll target the civilian.

MECs will grenade your soldiers if they are within 3 tiles of each other. Snakemen will gas them if they are within 2 tiles of each other, and then attack anyway. Sectoids mind control is very dangerous if one of your soldiers is closer than the others, stick close together when a sectoid is active so that if the sectoid gets in range to mind control, then everyone else is in range to kill/flashbang it

Stealth:

Stealth is a trap! It makes you think you can stealth the objective, but after several turns spent in stealth every enemy on the map wil lstart heading straight for you til they get close enough to spot you. Only use stealth to set up in a good position for the first engagement. You may think you can save time by stealthing close to the objective, but odds are you'll just end up pulling multiple enemy groups at once and end up trapped in a brutal firefight where you struggle to gain ground

If you aggressively engage enemy groups as soon as you see them killing them in 1-2 turns, then after killing 2 groups you can safely charge ahead and aggressively flank the remaining aliens without fear of pulling additional contact

Timers:

I hear a lot of rage about timers, but it's only an issue if you're playing defensively or trying to stealth it. Playing defensively is actually more risky than playing aggressively, and playing aggressively is safe if you have enough grenades, elevated guns, close range shotguns, or combat protocol, and you use them properly and know when it's safe to let an enemy survive a turn

The challenge of a mission is to dispatch the first 2 enemy pods with 4 turns. If you do that then you can rush the objective and if you make contact you can flank aggressively and dash and slash with your rangers. Try to make solid use of elevated fire on the first engagement and reliable damage methods like grenades and combat protocol early liberally for the first 2 groups. Grenadiers get 2 grenades if you equip one, and specs get 2 combat protocols. If you master the art of eliminating pods in 2 turns you have enough of these abilities for almost guaranteed 1 turn destruction of the first 2 groups you encounter unless they take up really awkward positions like tree or ridges.

Resistent the temptation to save these abilities for later, the first fight is dangerous because advancing could risk pulling a new group, but you get the advantage of catching the enemy out in the open and from a pre-prepared position. The second encounter is the most dangerous because you have to advance to trigger the enemy, meaning you don't have a fresh move, and you can't advance aggressively in case you pull new enemies. Don't take any chances on the second encounter, throw everything you've got at them. The third encounter is always the easiest unless there's more than 2 groups. You don't have so many reliable damage methods but you probably still have grenades on your assault and sniper, but you can use dash and slash, and you can aggressively flank, or just pull back if you have the timer and lure the enemy in so you get a fresh turn to engage them after they pursue. If you have the time then it's worth getting your sniper into an elevated position for the third fight, but it's not as necessary for the second since you should still have most of your grenades and combat protocols

When you get squad size 1 then you should never fail to eliminate the enemy in 1 turn, you should have 2 grenadiers which means you can bomb the hell out of the enemy if you really must. If you're really struggling then consider substituting the assault for a rifle til you get squad size 1, it just means it will take longer to get blademaster and shadowstep (lightning reflexes) on your assault which means April will be a bit harder, and it means you've one less surefire and reusable way of dispatching weakened enemies or the 4HP troopers

Destructable Scenery:

I've seen barrels in the blacksite which detonate for about 5 damage. Consider it to be a free super grenades since attacks are guaranteed to hit it even if disoriented. You can simulatenously do high damage and blow the cover of enemies, killing troopers and severely wounding anything else

Vehicles explosions do 6 HP damage. If you've got a strong enemy on a destructable vehicle, consider detonating it with 2 grenades, provided one of the grenades damage the enemies the vehicle explosion will finish it off. If multiple enemies are taking cover behind one vehicle... well, this is why we bring 2 grenadiers :)

Target Priority:

MECs if you have someone on a roof who hasnt used a turn > Enemies who can flank > Shockies if you don't have a revive > Snakemen > Commanders if they are accompanied by 1+ troopers/2+ troopers/commander+turret > Shockies if you have a revive > MECs who cannot flank you > Sectoids > lone trooper > faceless/zombie who cannot reach melee range in a blue move/shockies who cannot reach you in a dash

Evac:

Sometimes the game just really hates you. An enemy spots you outside it's sight radius, or you pull the second and third enemy packs at once, or a car outside your grenade damage radius explodes and kills one of your guys (never use a grenade within 10 tiles of a vehicle you are covering behind), or the enemy takes up position in indestructable cover, you fail to kill the, then more groups come patrolling over

If you are fighting more than one group then consider whether you can defeat them, or at least cause severe damage in one turn. It might be worth rolling some 85% shots if you really feel you must win the mission. But if you have a poisoned 1 HP soldier, 1 KO, and your revive protocol spec is panicking, and you've got 2 snakemen and a shocktrooper active, supported by 3 troopers, just get out of there it isn't worth losing 2 of your sergeants to that.

Press P to summon an evac sight, put it on your KO guy if you can, see if you can grenade and snipe the shockie if yo can't aggro him with your ranger, or take out a snakemen if you can. Try to position your remaining troops so the troopers cannot get a flank shot on your panicker without exposing themselves. Then next turn get the survivors to the evac and pick up the KO guy before you pull out

Now here's something interesting about the evac site, you can evac after you finish your move if you are stood in the evac site. So you moved one of your guys into the evac site on your turn, but on the enemy turn someone overwatched and your 1HP sniper who took 3 trooper shots last turn is gambling with his life if he tries to run the fourth one. Well, you can move your spec to the evac site, combat protocol the overwatcher to break the overwatch, the evac the spec and rush your sniper safely to evac as well. It's why you can pick up an unconscious soldier and evac the same turn (and why you drop the evac site on unconscious soldiers). This also means you can take parting shots on enemies if you used a blue move to get onto the evac point, hopefully for some extra EXP

If one of your dead guys has gear on him then consider carrying him to evac as well. I'd only risk it if you can get the evac site on his body though, because picking him up takes a turn and you really need all hands on deck to cover your escape

Finally, if you are on a mission to retrieve an object or a VIP, you don't lose out on the item or scientist/engineer so long as you evac them out of there, you only lose out on any supply rewards the mission offered. I think you might miss out on the intel in hacking missions though since you failed to secure the site even if you stopped the timer.

There are a number of abilities and items that work exceptionally well together:

Fire/Gas debuff combo - Fire disables abilities and gas drops aim by 30 and reduces movement. This leaves the enemies greatly weakened for a few turns and they'll typically die of the DoT if you leave them long enough. Very effective on the final mission where you can cripple enemy reinforcements then focus fire on the boss

Fire/Codex cripple combo - Fire disables abilities AND reloading. Codex disable empties the enemy's clip. The enemy can only hunker down til they stop burning, leaving them essentially neutralised. This is amazing for the final mission where you can cripple enemy reinforcements and then just ignore them and focus on the boss. Be aware that a magus psi op with an alien psi amp only has about an 85% chance to dominate a codex, but when it happens it's GG

Fire/Acid kill combo - The fire and acid bombs do decent damage. They also apply a DoT that does extra damage with Volatile Mix. If you're in a terrible situation with lots of enemies around and hardly and time left, consider hitting a group of them with Fire/Acid and relying on the DoT to finish them in a couple of turns while you focus on the other enemies

Grenade drop combo - Grenades can damage enemies and drop them through roofs for additional falling damage. Aim the grenade carefully to do damage to the enemies, take out the floor under them, and take out any other floors under there as well. Any survivors can be finished with even more grenades. If the enemy is on a car showroom roof try not to catch the cars in the blast as the car will detonate before the enemies land and wont do extra damage, whereas if the enemy is tough and survive the fall they will be sitting on a car that can be detonated with another grenade

Grenade salvo - Fire a grenade. if they survive fire another one. And another one. They great thing is they never miss and cannt be dodged. They're extremely useful on terror missions where you have to advance more quickly than usual and need to shock and awe anything that gets in your path, but this strategy pretty much requires improved grenade launchers, volatile mix and plasma grenades/acid bombs or you just wont get enough damage out with your limited supply of grenades to clear the map like this. It really is awesome between late May - late July where you can easily clear maps like this and you don't have to deal with any dangerous high HP enemies yet

Sharpshooter Rupture Fanfire Kill Combo - Rupture applies on every shot, so does special ammo. The general idea here is to rupture with a grenadier or psi operative, then use quickdraw> lightning hands > fan fire with your sharpshooter. With bluescreen rounds and rupture your sharpshooter can do 8 + their usual 6-8 pistol damage 5 times. Without even critting that's 75 damage on a sectopod in one turn! There's no real equivalent ammo for organic units, although there are few organic units with high HP and you really only need this combo for gatekeepers/sectopods. If you want to use it on the special enemy then consider equipping talon rounds for some additional crit damage, dragon rounds for +1 damage per shot, or tracer rounds to reliably keep hitting it as it teleports around the map. The only real problem is the long cooldown, you won't be able to abuse this so much on those 8 turn timer missions, so consider that when deciding whether to bring a ranger or a sharpshooter. They do excel with it on Supply Raids where they can wait on their cooldowns, and where rangers struggle to get into range though.

Grenade Faceoff Kill Combo - Soften, shred armour, and remove cover with a grenade. Then shoot the two highest HP enemies with the sharpshooter's quickdraw and lightning hands to bring their HP down more, then finish with a faceoff. Faceoff is the highest radius AoE attack in the game, allowing the sharpshooter to shoot anything it can see. Multiple sharpshooters using faceoff against exposed and weakened enemies can clear 10+ scattered enemies in a couple of turns reliably. Very nice on the final mission where there are enemies all around, your team is very scattered, and where grenades are currently very buggy and unreliable compared to faceoff

Stasis Lockdown Combo - 5 of your guys shoot, then the last guy who is a psi op casts stasis on the enemy to make it skip a turn. Then 5 more of your guys shoot and your other psi op casts stasis. Then all 6 of your guys shoot and if it still isn't dead you're doing something wrong. Excellent for dispatching powerful late game enemies like andromedon, sectopods, gatekeepers or the special enemy. You should be getting your first 2 magus psi operatives around the time these enemies start to appear and your grenadiers/sharpshooters can no longer carry the show by themselves reliably, and this gives you some amazing battlefield control compared to the unreliable specialist haywire protocol. You can have stasis in the midgame for archons if you built a psi lab early on a power coil (their power cost is high), pick up stasis as number one priority!

Mimic beacon lockdown combo - The poor man's stasis lockdown. You only get 1 mimic beacon, it takes up an item slot, and the enemy isn't guaranteed to shoot at it, although if your guys have good armour and cover and you left the mimic beacon in the open in range of the enemies then odds are they will shoot it. The advantage is you can use it without a psi operative, and even if you have psi operatives that have stasis on cooldown they can throw these anyway while they wait for the cooldown to finish. Very useful for the final room of the final mission, but I feel like the only time you would really need one in the rest of the game would be March/April and you just don't have enough faceless corpses to research/craft even one of these. You can get one after the second terror mission, but it will only be useful for the next 2 weeks before you get plasma grenades and can just grenade salvo everything out of May, June and July. Definetly bring them with you for the final room of the final mission though, they will save your life there and allow your psi ops to focus their stasis uses on the boss enemies rather than the other less dangerous enemies

Void Grenade Salvo Combo - By the time you get to late July your grenadiers cant quite finish the enemy in one turn anymore. You'll have to bring a couple of psi operatives along in place of grenadiers, but this harms your damage potential. However, the psi ops void rift attack not only does some decent damage in a medium AoE, but your psi op also randomly casts insanity on enemies in the void for additional damage and rupture. Since rift ignores cover and armour, you should use your grenades after you cast the rift for the chance at additional rupture damage applies to grenade damage. Rupture applie to DoT affects too, so a rupture enemy with acid will die if it doesnt have more than 6 HP at the start of it's turn! This is useful for keeping the momentum going after you bench 2 of your grenadiers and continuing to hit those turn timers!

Ranger slash evac combo - Kudos to Ronar for this one. If you need to make a slash to kill a sectoid or snek or something but your ranger will probably die if he misses the slash then put a evac flare on the spot your will slash from (before) you slash. You can then evac the ranger if you miss. You can also do it if you know the ranger will definetly be flanked even if they hit the slash. Only do this if you are sure you can do without the ranger for the rest of the mission, such as if you are dealing with the final 1-2 enemies

Hacking/Item retrieval:

Advance in the open, stay away from corners, you want to spot the enemy before they see you. When you spot the first group, get to an elevated position, wait so you have a fresh turn, then shoot the highest HP enemy and dispatch the rest with reliable methods. Hurry ahead but be sure to move into cover and only blue move. Engage the second group with the rest of your reliable methods. Get your sniper into a good firing position and advance on the objective rapidly, you can yellow move into full cover but only if you are <4 turns on the timer. Dispatch the 4th group aggressively, only hack the objective if there are <3 turns on the timer (you should do it when you have 2 turns left, in case you mess up your specialist positioning or the specialist panics with only 1 turn left. Unless you desperately need the specialist to finish a dangerous enemy)

VIP rescue:

Same strategy as hacking. After you eliminate the second group start moving rapidly to position your squad between the VIP and the extraction if you have time. Engage the third squad if you see it. If you still have explosives remaining the detonate a hole in the building wall and hack the door with a specialist so you can dash your VIP out and extract next turn. if you cant do that and the third group is still unaccounted for the move the whole squad to the VIP and engage enemies if necessary. If you killed the third group then rush your assault in to free the VIP and leave everyone else at the extraction, when the red flare appears position everyone all around it on overwatch, then finish the enemy reinforcements next turn and evac. be aware you cant create new extraction points so it's all or nothing. Also if the extraction point is on a roof and you damage it then it reappears elsewhere. It's really embarassing when you have 2 turns left and decide to stay a bit longer to finish the last enemies, then fire damages the evac point and it reappears 2 turns away and all your guys get captured by the corpses of all the enemies you killed

VIP escort:

Same strategy as hacking and rescue. You have 12 turns so this is quite easy. The AI tends to play defensively and can be annoyingly stubborn. This is generally an easy mission to do thanks to the long timer limit but as with VIP rescue be aware you cant create new extraction points so it's all or nothing

Dark VIP:

Incomplete section

Supply convoy:

Very very easy. You can make evac sites, you have no time limit, you start concealed. Take your time to set up the first ambush, and advance carefully so you can pull back if you trigger a group badly and wait for them to come to you, giving you a fresh turn to engage, but dont stay in stealth too long or all the enemies start patrolling towards you. Be careful about using explosives here, supply crates glow blue and you dont want to damage them. Fire can damage crates

Terror:

This can be a bit random. Civvies can turn into Faceless, but I think there's only 1 or 2 on the map so if you killed 1 its much safer. Faceless can attack the same turn they transform if they transform on an enemy turn. If you try to rescue a civvie who is really a faceless it transforms but wont attack until it's turn, so only activate a civvie on your first turn, or if you have everyone close together (faceless cant take cover so you dont need to move to flank)

The enemy can only kill 1 civvie by mistakes, unless they accidentally kill one with grenades or poison clouds. Since its mission failure if the enemy kills 8 civilians, you essentially have 8 turns to clear the map, assuming the AI can kill one every turn.

Killing groups wont slow the rate they kill civvies, its always one per turn. Try to prioritise saving civvies so you dont get a faceless charging into your rear later. Of course, you should kill enemy groups as soon as you see them as usual, it's even more important than usual to eliminate groups as soon as you make contact this time, but ideally you want to avoid triggering enemies and focus on getting 6 civvies saved ASAP. You can see civilian rescue circles even through fog, so try to pick the area with the most civvies and aggressively clear it so you can save lots of civvies in few turns. The mission becomes essentially a supply convoy mission after you rescue 6 civvies, but if you have rescued 6 civvies, killed 2 groups, and there are more civvies alive consider advancing aggressively as the AI will still shoot a civvie every turn, meaning you only need to clear all but one of them on contact

Failing a terror mission means you lose the region and radio tower if you built one. You can reestablish contact but its just more wasted time and resources you should be using to delay the Avatar project. You don't get any rewards for these so it's basically a monthly damage control mission

Defend device:

These are usually really tough, and the AI gives their position away by attacking it. They can only attack it once per turn until you spot it so you've got about 8 turns to clear, same as a hack, and thats assuming there are enemies who can attack it. I'm not sure if they prioritise hitting in exactly once per turn, or skip attacking it so attack one of your soldiers instead, but it might be safe to let an enemy survive if you cant finish it since it will probably attack the device instead of you. I've only had one of these missions, and Bradford told me reinforcements are coming and a weird purple psi orb appeared nearby, but then it disappeared and did nothing. Since you know where the enemy are, try to avoid spotting them so you can get close and flank with your shotgun and specialist

Device destruction:

Like hacking except you need to destroy the device. All attacks are guaranteed to hit but unless you roll high damage then it will take 2 attacks, be prepared for that.

Blacksite:

Get on one of the rooftops nearby and camp there for a while, you can take out 2 groups and probably a turret no problem

Approach the main building using the trailers attached to the train to cover your approach, chuck a battle scanner over and chances are you'll see a group of enemies standing around in front of the building, grenade it but be careful not to damage the building wall

Get on the roof and get everyone together in a tight block near the ladder. Move a few of them towards the middle of the roof close to the skylight, but not too close you don't want to spot enemies yet. Wait til you have a full turn then move someone up to the skylight near the ladder. You will spot probably 2 groups of enemies who scramble for cover. Grenade and gun them all down with the height advantage, DO NOT let a MEC survive or it will kill you all with grenade salvo

Drop down inside and make sure the room is clear, then get back on the roof and move towards the extraction point, there will be 2 more groups over there probably, make sure to throw battle scanners so you know where they are, then grenade them and kill with the height advantage

If you have any explosives left blow a hole through the wall into the vial room. Leave everyone at the extraction point and send someone to stand next to the vial. End your turn then grab the vial and sprint towards the extraction. A flare will likely appear to signal enemy reinforcements, you can kill them for EXP if you like by camping near the flare on overwatch, or just extract everyone on your next turn

DO NOT try to stealth this mission, the first 2 pods are limited to the first half of the map before the train but will make a beeline for you when you go past the train. When you're past the halfway point of the main building the 2 pods inside will come out to move towards you. Eventually you will be stuck with 4 pods close by and any movement will activate them and then you have to fight in a really dangerous situation.

AVENGER defense:

Incomplete section.

UFO raid:

Incomplete section.

Base/Map

The AVATAR project is too dangerous to leave alone. Unfortunately the base strategy is just sat rushing on steroids.

Consider the rooms as a 3x4 grid. The first row is row A. The first room of Row A is A1. The second room of the second row would be B2

Get a Guerilla training school immediately in A1, you need it to train 3 heavies quickly, 2 for the missions and a spare in case one gets wounded. Get 1 of every other class type, then a fourth grenadier, then train evenly, keeping 2 more heavies than every other class. You also need it for the squad size upgrades, and getting squad size 1 in March makes April much easier. It's essential for May

A2 needs to be a power plant. B2 needs to be a workshop. B1, B3 and C2 need to be communication relays which you staff with gremlin drones from the workshop. The other rooms can be anything you want

Again, you need to prioritise engineers. You really must win missions that give them as rewards, prioritise them on your scans, and buy the extra engineer every month from your HQ in the home region (they cost 175 supplies but you get a supply drop right after the council report)

You need engineers to clear rooms, build rooms, and staff rooms. Engineers staffed in the workshop can operate 2 gremlin drones, which can staff adjacent rooms. A power plant gives 3 power, plus 2 for every engineer or drone inside, and a communication relay gives 1 extra region, plus 3 for every engineer or drone inside. Both can be upgraded for additional engineer/drone spots, thats why you have them positioned around the workshop, since every engineer in the workshop generates 2 drones, meaning they can do the work of 2 engineers

You must expand across the world quickly. This way you can avoid UFOs that are hunting you, and can raid new blacksites soon after they appear. Your first priority should be to make pathways all through the world. There should not be a single region you cant reach withour making contact once. For instance, if you have West Africa and Mexico, then if a blacksite appears in Brazil or South Africa it only takes 5 days to make contact with the region and take the site down.

Expanding requires huge amounts of intel unless you have a radio tower in the region you are expanding from. I recommend you get a region in every continent ASAP, and make sure you are never at your maximum regions, and every region has a radio tower in so you can immediately expand

Radio towers also vastly increase income. The problem with this strategy is you will be broke for a long time, and May is hell, but it really is essential that you get the avatar project on lockdown right away. Mag weapons are expensive anyway, and you can handle March and April with beginning items using my aggressive strategy. You should be able to potentially expand to any region with just two communication relays built and staffed, and you'll need to build another one next month if you are unlucky with blacksite locations, but then you have the breathing room to buy nice things for your squad

Don't build labs. Even without them you'll end up researching awesome things before you can even afford them

Everything else can wait til you get the Avatar project under control

Research:

You want the first weapon research so you can outfit your sniper with a scope, and your heavies with ammo reloaders. Give specs and rangers any spare scopes. This transforms snipers from 85% shooters at elevation to 100% at elevation, or 100% close with a pistol, and you really need those reliable shots fast. A ranger with a scope can pull shotgun blasts at med-long range with assault rifle accuracy, and get 100% shots from 5 tiles away on flanked or exposed enemies

Next is the chip so you can expand to the blacksite. Then you want the chip so you can raid the blacksite at the end of March/start of April. Then you want the radio towers to expand farther. I'd recommend mag weapons and armour after that, though you wont be affording any anytime soon. It would be nice if you can scrape together enough for a mag assault rifle, pistol and shotgun in May

Still having trouble? Here's a step-by-step on how I won this difficulty

Gatecrasher:

If there's a building near the park then get everyone on it. Kick off the ambush from up there, then take your shots and use overwatch if you cant shoot. With the height advantage your aim should be very high even with overwatch or vs half cover

If you cant engage from a roof then get everyone up to the 3 trooper group and in full cover. Set 3 people to overwatch and kick off the ambush with a grenade to ensure any 3 damage shots will still kill. Odds are the enemy will get to shoot back but shouldn't be able to flank. Camp in overwatch for free shots on the second group then try to kill the officer quickly with grenades and flank shots. If anyone dies then restart til you pull it off. This mission sucks since you only have rookies

March:

Build a Guerilla Tactics School immediately, you won't have an engineer to build it faster til you complete the mission for one but its a good start. As soon as it's ready start training grenadiers. Also begin excavation whenever you can.

Research the chip, then communications, then trooper. This will make sectoid autopsy instant so do that as well. Then research the officer and radio which you'll be needing in April. Research modular weapon and hybrid materials. You want plated armour first but without the alloys you cant do it, so research mag weapons til you can switch to armour

You should prioritise scanning for engineer > rookies > intel > supplies > materials > everything else

Your first missions are gonna suck. Restart if you fail one in March you cant afford it. Bring a flashbang along and don't stick it on the ranger or grenadier. Stick to the rooftops, try to get your sharpshooter in a position to provide fire support as the team advances along rooftops. Stay away from the edges so when you see the enemy you are close, that way you can use grenades if you need to and have high accuracy. See if you can feed kills to your grenadier with the grenade launcher if you are on the last group or two and have plenty of grenades left. Replace the other team mates with grenadiers as you produce them in the OTS, replacing your specialist first, then sharpshooter, then ranger. If someone gets mind controlled flashbang the sectoid. If it was your flashbanger then blow its cover with the grenadier and shoot with the sniper. If it's still alive then rush the ranger in to slash it. If a grenadier dies in March then restart you can't afford it yet

March Terror Mission: While faceless don't hit that hard, they're still pretty dangerous for you at this point. Build 2 battle scanners to bring along. Try to scan groups of civilians and keep your distance from any you cant scan. Advance quickly but carefully using the battle scanners. This will be a tough one but the enemy doesn't have much to use against you yet.

When you have to choose missions, always prioritise the intel. You need it for rapid expansion and it can be easily converted into supplies in the black market, or items that you can sell for supplies. Or materials you might need to buy a new upgrade, building or research. You should definetly stop alien encryption or it will basically stop your expansion for a month, and UFO hunter since its hard to pull those off without people dying and everyone else in sickbay. I would take the engineer reward in March/April over intel though, you need them fast for rapid excavation in April and building in May

April:

This month is gonna be about as tough as March. You've got vipers, mecs and lancers on every mission to deal with and grenades wont do enough damage. Stick to the rooftops, blow cover with grenades and fire down. You should be using all grenadiers and still training more as replacements. You should have squad size 1 and get blast padding on all your grenadiers, you can swap it out later but you just cant reliably kill enemies before they can fire yet and you NEED the extra survivability.

Continue excavation and start work on a proving ground by April 10th. Build a power relay but make sure you will be able to get a workshop next to it, and a comms relay next to the workshop in May.

Prioritise buying the engineer from HQ and starting construction of the proving ground. You can use the remaining resources to work on the power relay, workshop and comms. See if you can get the workshop in the middle of level 2 so you can use it to excavate all around itself with gremlin drones

You need to expand into the blacksite region this month, preferably before the supply drop, as the additional supplies pay for your building upkeep

Prioritise scanning: Engineer > Black Market > Scientist > Expansion > intel > Supplies > Everything else

Black Market: Consider buying supplies with intel if you need to in order to keep your construction from stalling. Don't buy anything else as you need the intel for rapid expansion in May+. The black market gives extra money for 3 different types of item every month so try to only sell it when it's VERY INTERESTED status. If alloys are VERY INTERESTED consider buying some to sell back. Don't sell all of your alloys/elerium as you will be needing them in May/June. Keep at least 40 as you can expect more from supply raids. You can sell things that arent VERY INTERESTED if you really need the cash, prioritise corpses but hang onto those faceless and keep 4 trooper corpses for plated armour later

April Terror Mission: By this point you can afford to lose 1 or 2 grenadiers. You should have more at specialist level in reserve and your main team will only be corporal/serg at the moment. You MUST win this mission, the muton corpses are essenial for this guide. Same deal as before really, but you will now have grenadiers with blast armour and maybe plated armour if you got lucky with scientists and alloys. Get those mutons down fast before they can retaliate. You can probably take a faceless punch to the face so you can advance a bit more rapidly now.

Begin the muton autopsy IMMEDIATELY after you finish the terror mission

May:

The first part of this month is the hardest part of the game. You now face advanced ADVENT troopers and mutons on your missions.

Finish the muton autopsy, set the plasma grenade project in the proving grounds and assign an engineer, and buy the improved grenade launcher. Finish research on plated armour if you haven't done so yet and buy that as well, giving your grenadiers all battle scanners in their extra slots. Consider crafting a mimic beacon to help you through the first week or so

Research psionics next, then mag/gauss weapons for the cannon upgrade either at the end of May or the start of June.

When the proving grounds plasma grenade project is finished remove the engineer to work on excavation, begin the improved explosives project, and then start producing experimental grenades.

Continue work on the power relay/workshop/comms you really need them finished by the 10th. Build a psi lab as well it must be ready and upgraded by the end of the month. Build a second power relay if you must. Garrison the power relay and comms with gremlin drones from the workshop. You should have 4-5 engineers by now so you can staff the psi lab and workshop but still keep excavating

Before the end of the month you must begin work on 2 psi operatives or you're gonna struggle in July/August. Priortiise Stasis, Sustain, Domination, Null Lance, Void Rift and Fortress in that order as they are the most important abilities

You must also begin expansion towards the alien facilities, building radio towers as you go to minimise the intel cost

Your scanning priorities are Engineer > Expansion > Intel > Scientist > Supplies > Materials > Everything Else

Missions will be tough until you have plasma grenades and plated armour. Then things will really get much easier as you can bomb the enemies away with 5 damage high radius grenades and potentially take a muton crit but survive. Your grenadiers should be getting to Lieutenant/Captain level, get Squad Size 2 as soon as you can. The additional grenade and extra damage/radius you'll get from these promotions is awesome. If you have the supplies consider buying the +25% exp from GTS as it is retroactive and Captain Grenadiers are worlds apart from Lieutenant Grenadiers

Hit the blacksite if you need to stop the avatar timer at 3 days, you should be getting close to the first alien facility soon but dont hit it til the timer is at 3 days again

May Terror Mission: Lol

June:

Don't you just love the Summer? You now have Captain grenadiers with plated armour, mag cannons, 7 damage plasma grenades with insane radius, and probably 1 or 2 10 damage acid bombs. With the extra item slot you can scan ahead with scanners as you traverse rooftops and make blind grenade shots on enemies you cant even see, and never again run into an unexpected group.

This month is extremely easy, take the time to work on your base. Try to finish or nearly finish excavation, get your second power relay if you havent yet. Build an AWC and start retraining your grenadiers for shredder ammo. Consider beginning construction on a second comms if you're getting close to using all your contact. See if you can get a shadow chamber finished by the end of the month or the start of July, you will need it in July

Keep on expanding to reach all the alien facilities. Build radio towers as you go but dont build them in dead end areas, you only need them to reduce the intel for expansion to adjacent areas so theres no need to build one when theres no region beyond that that you need to connect to. A good way to do it is to build a pathway of radio straight through the Euro-Asia continent, put one in Egypt, and on in Brazil and Mexico so you can expand to the other regions at the cost of only intel. Towers will not help you expand between the Americas and Euro/Asia/Africa it always counts as double intel for the jump

Scanning priority is Engineer > Expansion > Intel > Scientist > Supplies

Research priority is MEC autopsy > Elerium > Power Armour > Beams > Cannon

See if you can do the bluescreen protocol project in the Proving Grounds, you'll need it for late July, all of August

Mission strategy is SHOCK AND AWE. Bomb it into oblivion. Consider taking shots only for the chance to get loot but use grenades to finish if you must rather than taking fire. Gas grenades don't destroy computers/item boxes so bring one or two on those missions in case the enemy hugs the objective so can take them down and take the poison damage to get the objective. By now you should be getting your first grenadier majors which are excellent for peeling enemies off of objectives and finishing archons with hail of bullets

July:

Andromedons start to appear in this month, and if you finish beam weapons before the month ends you will see sectopods as well. You really must get the shadow chamber finished and be prepared to deploy psi operatives whenever you see andromedon/sectopod or gatekeeper in the enemy loadout, and you will need them for the July terror missions because there's gonna be chrysalids and it takes a fortress psi op to advance and take their poison if they successfully ambush you

If you go up against an andromedon without a psi op it could be bad. They've plenty of armour and HP so it takes a concentrated grenade barrage to bring them down fast. You might not be able to do it if the other mobs are stood too far from it, or if it's stood too close to an objective. You need your psi ops to provide stasis. If you go up against a sectopod without psi ops to use stasis than chances are you will wipe

You will be finishing power armour and beam weapons this month, and maybe cannons if you are lucky or built a lab. They're expensive so save your cash and supplies for them. You should already have all the buildings you need in your base so focus on expansion. Build towers to aid expansion or to get any good continent bonuses. Consider buying some more GTS upgrades, the grenadier upgrade is vital for July+, and there are other nice upgrades to get now you can afford them

Same research path as June. Consider working on a couple of WAR suits in the proving grounds for your psi ops, and then work on experimental weapons to try and get blaster launchers or shredder cannons for them, it gives psi ops an additional form of damage to help keep up with grenadiers in damage dealing

You might also consider keeping an eye out for a high level sharpshooter in HQ. I didnt bother with them, but its not a bad idea to swap out a grenadier for one to help bring down high HP enemies or providing some very wide range AoE damage. It's also not a bad idea to bring along bluescreen rounds on your psi ops instead of grenades to help with those sectopods towards the end of the month, and gatekeepers in August

Be sure to take out all the alien facilities as soon as you can hit them all, they take longer to build the fewer of them the aliens have

Same scanning priorities

August:

You'll start seeing Gatekeepers and Sectopods regularly now, but your psi ops should be fully trained with 2 more beginning training just in case.Everyone should have beam weapons and your grenadiers should have Warden armour and psi ops have WAR armour and bluescreen rounds, preferably blaster launchers as well. All your grenadiers should have respecced using the AWC for shredder ammo and be colonels. Consider swapping out one your of colonel grenadiers for some of your captain/major grenadiers you swapped out for the psi ops, it's good to have backups trained up. You should really be keeping an eye out for a sharpshooter recruit in the HQ or black market, its good to have one on the last mission for the final room as grenades are currently unreliable in there

Finish expanding across the world and start your shadow chamber research. Build a skulljack in the proving grounds and skulljack an officer then take out the codex, I recommend doing this on an alien facility or supply raid mission, or bring one along on a hack/item retrieval so you can ambush enemy reinforcements with it after you get the objective. Without a specialist you cant reliably skullmine with these so only use them to progress the story

Hit the foundry and portal when you can and continue your shadow chamber research. The avatar project bar will plummet all the way to the bottom never to recover. Be very careful when you skulljack a codex, you need at least one psi ops to have a stasis, make sure you have a mimic beacon on a grenadier just in case and everyone is reloaded with plenty of grenades and no other enemies are around. If you trigger this thing with other enemies around or no means to direct fire away if it gets a turn its gonna suck. Odds are if it does get a turn it will just mind control and a psi op can dispel it with solace but if it casts void your entire team will be in medbay for a week

The moment you get a gatekeeper corpse autopsy it. Then when you get a second one buy the alien psi amp. This will make domination very reliable.

I'd mainly scan for intel at this point. It will allow you to skip missions after this and keep resetablishing regional contact while you grind out more proving grounds projects or psi operatives if you want to

You should have everything ready for the tower assault by now. Consider stalling it to get more psi ops, acid bombs, WAR armour/blaster launchers, guerilla tactics school upgrades, sharpshooters from the HQ, or weapon upgrades/PCS from the black market.

Psi Ops make the final mission a breeze, the aim PCS and scopes turn them into deadly shots, the mobility upgrade is good for chasing down those annoying boss enemies in the final room who wont stop teleporting as well. Repeaters are great for sharpshooters, your grenadiers may have to take some shots in the last room if hail of bullets are on cooldown and they cant get a line of sight with the buggy grenade angles to definetly get them scopes and aim PCS if you plan to bring them.

I'm sorry for making you rely heavily on grenadiers but they're really not that good on the final mission aside from shredding armour. Their grenades bug out a lot and cover is mostly indestructable, so you end up using hail of bullets/rupture to soften the boss enemies, and pistol sharpshooters/psi op cooldowns obliterate them. A good lineup is 2 grenadiers, 2 sharpshooters and 2 psi ops, or 4 psi ops and 2 sharpshooters but make sure you bring shredder cannons/blaster launchers for the final room

It's not a bad idea to make experimental armour and bring some stasis vests, the final room is a real clustercup and even with mimic beacons, dominated codexes, fire grenades, AoE damage and stasis it's hard not to take fire from enemies, rushing melee enemies, having to rush out to kill the boss enemies when they teleport far away at 5HP to heal etc and stasis vests really give an additional level of protection for the final fight. I wouldn't bother with bluescreen rounds or scanners, you dont see sectopods in the final room and gatekeepers only appear solo and its usually easy to spot the enemy since theyre all over the place

I'd bring stasis vests, mimic beacons, grenades and WAR suit shredder/blaster launchers to help with that final room since everything up to that point can easily be handled through hail of bullets, sharpshooter, commander and psi op cooldowns and then just wait in overwatch til they recover

You can skip missions to avoid the risk of someone getting killed, even if you lose a region. Just make contact again immediately and keep building radio towers if you have excessive amounts of supplies. You still want to stop UFOs and avatar breakthroughs though so you can keep killing time for longer without much risk. I'd also do supply raids for the elerium cores you get at the end, and maybe guerilla ops if there's a sharpshooter reward

As you can see, the game is all about extreme aggression, using elevated shots, grenades and special abilities to guarantee you destroy the enemy groups fast. If you can get the first 2 down you can typically advance and flank the final group without fear of triggering additional contact. This is only necessary til mid May when you can finally grenade the world

Grenadiers are currently extremely overpowered. Sharpshooters arent far behind. And while psi operatives are overpowered you'll typically only get 2 by the end of the game. I expect they'll all be getting the nerf bat before long, or else specialists/rangers will get a buff.

Get a GTS and start training grenadiers ASAP. Ditch your specialist, then ranger, then sharpshooter as you replace them with grenadiers who are far more dependable in the early game. Try to get Squad Size 1 before the March terror mission. Begin work on a proving grounds no later than April 1st for plasma grenades later, and get plasma grenades, improved explosives and experimental grenades after you autopsy a muton. Also buy improved grenade launcher after the autopsy

Focus research on plated armour first so you can get battle scanners on all of your grenadiers. Priortiise muton autopsy after the April terror mission. The only mag weapon you need is the mag cannon but by the time you get it you will probably be finishing everything with plasma grenades anyway.

Then make sure you have an upgraded psi lab no later than the end of May so you have 2 psi operatives for August. Any other supplies you get should go into engineers, and building a workshop/power relay/comms to allow you to expand rapidly to hit the alien facilities fast and increase your income.

This guide is far from complete, I lost my squad to a burning evac site, then didn't keep an eye on the UFO and ended up in an impossible fight. But once I advance farther I'll update the guide

I welcome advice and constructive feedback. I hope my guide was helpful!

Good luck Commander Ironman

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Special thanks:
Patrick Colasour
AfroDuck