In Imperator Rome, each military tradition group comes with a predefined unit composition that the AI will always try to stick to. You may have noticed this during gameplay, but mercenaries do the same thing based on the culture of the province they're from. Typically, this is made up of 3 different types of units to fill the Primary, Secondary and Flanking cohorts. If you follow the recommended counter, you should be able to crush whatever culture group you're facing.

If you want to mod any of these values, you can find them stored in "\ImperatorRome\game\common\military_traditions".

Before we begin, we need to cover a few basics. Your three main sources of troops are Levies, Legions and Mercenaries. Here I'll answer what they are and when to use them.

Levies
These are troops that are conscripted directly from your core population. They are incredibly cheap money wise, as their true cost comes in the form of reduced output of your population. A conscripted citizen cant do any research, nor can a conscripted freeman provide any additional manpower. The amount conscripted from a region is the number of non-slave pops with an accepted culture, multiplied by the levy size multiplier. So a region with 100 pops and a levy size of 10% will provide 10 levy troops, and likewise have the provinces output reduced by 10% when those levies are raised.

In the early game, these will likely make up your main force. Especially if you're playing a poorer nation. It's not good to rely on these forever as they do give you war exhaustion every time they are raised, and it increases if they're raised for longer than a year. However they are great for quickly responding to threats, as you can raise them instantly in a province and they'll have full combat morale.

The actual composition of the levy is determined by two things: the culture of the population and their class. If you have a lot of nobles & citizens, your levies will contain a lot more advanced units such as heavy infantry. Otherwise, if you have a lot of freeman or tribesman, you may find your levy ranks filled with cheap units such as light infantry or archers. Each culture has a different composition as well.

The leaders for levies will be the region's governor, or if you're a tribe: the clan chiefs. Their military skills can be questionable at times, so you may find yourselves with low level generals.

You can conscript these from the military screen or by using the levy mapmode and clicking on a light red region.

Mercenaries
These are troops that are hired via the map or the military screen. They are expensive, but they have two great advantages. Firstly, they don't use any of your manpower so you can run them for as long as you have money. Secondly, they can have really skilled generals. Having high skilled generals makes sieges go way quicker and gives you a huge dice roll advantage during combat.

If you have the money for them, then use them! Chances are you'll be relying on mercenaries for a large part of the early and mid game.

As for composition, that's determined by the culture of their home province, so a Gaulish mercenary will be bringing chariots and a Greek mercenary will be packing heavy infantry. The price of each unit affects the mercenary hire cost as well, so you may have to cheap out and higher a merc stack with suboptimal units.

One catch is that mercenaries are uniquely vulnerable to being outbidded by your enemy. While I'm not sure the AI does this, if your opponent has a lot of money it's possible they'll hire your mercenaries and leave you empty handed! Luckily, you can do the same to them, so if you're fighting a weaker enemy that's spamming mercenaries, you can just pay them off.

Legions
These are professional troops raised from your population. Like levies, they can only have as many troops as their home region supports. Also, you can only create legions when you have the correct Laws and potentially even require the Cohorts invention from the military tree. Monarchies can change their law to raise legions straight away, but Republics need to go through an event chain that randomly pops up during gameplay.

Legions are the strongest and fanciest troops in the game. Since you can hand tailor their composition, you can stack them with the most powerful troops in the game, provided you can afford it. Additionally, their armies have a plethora of legion traits that give moral & discipline buffs. You can also hand pick their generals.

Once you have access to these, I'd recommend building a stack with heavy cavalry and heavy infantry. It should be your ultra reliable hammer to any threat.

Levy Composition
Roman:
55% Light Infantry
30% Heavy Infantry
15% Light Cavalry

Italic:
60% Light Infantry
25% Heavy Infantry
10% Light Cavalry
5% Chariots

Best Tactics
Bottleneck
Shock Action
Triplex Acies

Overview
Their standard levy template tends to hold out for a very long time, winning usually on morale more so than casualties, as both their core units have morale bonuses. This translates to winning fights that usually shouldn't be won.

They also have reasonably powerful bonuses for their Light Infantry and their Light Cavalry, so it's possible to use exclusively Roman levies for a long time.

Starting out, they can grab trade goods to have access to really powerful levies right at the start of the game. Those goods being Leather, Base Metals, and Iron.

Later in the game, their Heavy Infantry are some of the best in the game. Legions made up of Roman heavy infantry are something to be feared.

When fighting Romans
Since the Romans bring a tonne of high morale levies to the fight, beating them will largely come down to picking your engagements correctly, as they will win out on morale on an even fight. Heavy Cavalry should make quick work of the light infantry, but they'll struggle once they come up against the Roman heavy infantry, so be sure to make your secondary line filled with your own Heavy Infantry. If possible at all, Horse Archers and War Elephants are a good way to beat them.

Trees
Carpet Siege Tree
Heavy Infantry + Strong army tree
Cavalry + Barbarian Traditions Tree
Light Infantry + Hill bonus tree
Navy tree

Levy Composition
Greek Minor:
50% Light Infantry
10% Archers
40% Heavy Infantry

Cretan: (Crete)
75% Archers
25% Heavy Infantry

Macedonian: (All the major Greek states are Macedonian)
50% Light Infantry
35% Heavy Infantry
15% Heavy Cavalry

Epirote: (West Greece)
40% Light Infantry
40% Heavy Infantry
20% Light Cavalry

Thessalian: (Central Greece)
50% Light Infantry
25% Light Cavalry
25% Heavy Cavalry

Spartan/Argolian (Southern Greece)
50% Light Infantry
50% Heavy Infantry

Bosporan: (Crimean)
60% Light Infantry
30% Light Cavalry
10% Heavy Cavalry

Cyrene: (West Egyptian)
40% Light Infantry
20% Heavy Infantry
40% Camels

Magna Graecian: (South Italian)
50% Light Infantry
35% Heavy Infantry
15% Light Cavalry

Dacian:
55% Light Infantry
15% Archers
20% Heavy Infantry
10% Light/Heavy Cavalry

Best Tactics
Bottleneck
Shock Action
Phalanx

Overview
Greeks levies are similar to Roman levies, except they get access to Heavy Cavalry which IMO are a lot more fun! Heavy Cavalry will make mince meat of many of the cheaper units you come across, and they're only really countered by heavy infantry.

You can get access to some of the best heavy cavalry in the game by mixing the Cavalry tree with the Persian Rural Tradition heavy cavalry tree.
+40% offence and +25% discipline is not to be scoffed at!

When fighting Greeks
The best stack to use when fighting Greeks is usually your own Heavy Infantry + Heavy Cavalry/Horse Archer stacks. If you're running Legions with only those two units you should be able to blast your way through most Greek levy armies.

If you have access to War Elephants, consider placing a few in your primary or secondary rank.

If you're playing as a Persian nation, especially consider bringing a pure heavy cav + horse archer stack.

Trees
Cavalry + Light Infantry tree (Gives you access to Persian traditions which can stack to give you extremely powerful heavy cavalry!)
Fortress + Cavalry tree
Heavy Infantry tree
Hill fighting tree
Slave raid navy + levantine tree
Heavy ship tree

Levy Composition
Iberic: (Spain)
20% Light Infantry
40% Archers
20% Heavy Infantry
20% Light cavalry

Celt-Iberic: (Spain)
25% Light Infantry
30% Archers
20% Heavy Infantry
5% Heavy Cavalry
15% Light Cavalry

Gallic: (France / North Italy)
40% Archers
35% Heavy Infantry
10% Chariots
10% Light Cavalry
5% Heavy Cavalry

Belgae: (Northern France)
35% Light Infantry
40% Heavy Infantry
15% Chariots
10% Light Cavalry

Britannic: (Britain)
55% Light Infantry
20% Heavy Infantry
25% Chariots

Pannonian: (Central Europe)
40% Light Infantry
40% Heavy Infantry
15% Light Cavalry
5% Chariots

Illyrian: (Balkans)
60% Light Infantry
25% Heavy Infantry
15% Light Cavalry

Germanic:
50% Light Infantry
25% Heavy Infantry
25% Light Cavalry

Overview
Barbarian levy stacks are very decent in that they'll bring archers lined with heavy infantry with the occasional heavy cavalry. However that's only in the larger nations, the smaller ones will usually only have light infantry & light cavalry.

Barbarians get access to a very powerful +25% combat bonus in forests very early in their tradition tree, as well as +25% combat bonus in plains/farmland at the end.

You can get access to some extremely powerful Heavy Infantry if you instantly go down the Heavy Infantry/Roman tradition tree.

Barbarians are also one of the few cultures to field chariots. Chariots are very much a poor man's heavy infantry. If you go down the Brittonic tree, they should steam roll any light infantry/archers you come across.

Playing as a Barbarian
When you start out as a Barbarian, you'll find yourself significantly behind in research compared to the rest of the world. This is because your tribal government starts out with a 50% research penalty, and almost zero research production to boot. This means to be competitive, you have two options in front of you: rush to becoming settled & civilised, or embrace the pain!

Centralised
It's possible to become civilised in less than 30 years game time. If you head down the route of centralisation, I'd recommend picking Monarchy during the reform mission tree, as this will allow you to raise a legion fairly quickly. Make sure to max out your research points so that you can catch up. Once you have access to a legion, fill it exclusively with heavy cavalry! This will let you steam roll over the other tribes!

Gallic, Belgae and Pannonian cultures get access to a very powerful unique military innovation tree as well. Contrary to appearances, the Celts had very advanced ironworking.

Decentralised
If you choose to embrace the pain and go full decentralisation, you'll have an interesting journey ahead. At full decentralisation, you'll have a massive +15% levy size and +25% morale of armies. It's fine to use levies as I'd recommend razing any cities you come across as well (army action) as this will be your main source of technology. Once you've conquered them, destroy the cities entirely! Tribesmen & slaves are all you'll need in your empire. Only if the city is filled with your culture might I'd recommend keeping the city, as that will increase the quality of your levy, otherwise the city will just act as a constant source of unrest.

Becoming a migratory tribe will also allow you to spawn huge stacks of light infantry in exchange for stability, via the migration feature. These stacks are free forever, and can even be used to convert & assimilate up to 9 pops instantly at a time. These stacks dont respect borders either, you can send them into any country. They can raze any unfortified city for technology or pillage it for money. You can even use these stacks to offensively colonise any territory you've occupied in a war. If you pillage or raze a nation three times this will automatically start a war with them. If you don't own any provinces, you can peace out instantly at any time.

How clan stacks work
As a tribe, you'll be using a lot of levies. Tribes tend to divide the levies you raise between each clan chief, meaning you could potentially have 4 stacks with only 2 units each out of a single region. Make a note of your clan chief with the highest military skill, as his stacks will determine the tactic used in battle.

Also important to note, when sending multiple stacks into battle only the topmost stack will engage first and every other stack will be treated as reinforcements. The order of the stacks in a province is decided by when they arrived, so if you want to change out the order, you'll need to move stacks into a province in the order you want them to engage.

When fighting Barbarians
Most Barbarian stacks tend to be trash units, so you should be able to get away with using cheaper unit stacks against them. Otherwise just bringing heavy cavalry will steam roll over them, however it does usually come down to a war of attrition. They'll often have enough money stacked up to bring in multiple mercenary stacks as well, so if you up against a group of them you might find their army is a lot larger than you were expecting. If they have a city, they might be bringing more advanced units so beware! Especially against the Gauls.

Trees
Heavy Infantry + Roman tradition tree
Light Infantry + Archers + Terrain combat tree
Chariot Tree
Light Cavalry + North African Tree
Manpower Tree

Levy Composition
Punic:
30% Light Infantry
10% Archers
20% Heavy Infantry
25% Light Cavalry
15% War Elephants

Numidian:
45% Light Infantry
10% Heavy Infantry
40% Light Cavalry
5% War Elephants

Overview
The main contender for this Tradition tree is Carthage, and it has some pretty good bonuses that compliment Carthage's play style. Good navy buffs, cheaper mercenary stacks, several war elephant, heavy infantry and light cavalry combat buffs. All in all a pretty good tree.

They have access to one of the most powerful naval trees in the game. With already pretty amazing buffs, their tree lets them jump straight over to Levantine traditions which also has a navy tree. And then that tree lets them jump over to Greek traditions, which also has a great navy tree. They can effectively spend the entire game picking nothing but naval trees.

You also get access to a +15% plains combat bonus very early, which is great considering how common plains battles are.

North Africans are unique in that they get plenty of easy access to War Elephants and a 10% discipline buff for them. War elephants are the heaviest unit in the game and as such they tend to steam roll over anything they come across. Only archers & heavy infantry are really capable of damaging them. Avoid bringing them to sieges though, as they only bring enough food for 3 months and will quickly start attritioning the whole stack.

Playing as a North African
Carthage
When playing as Carthage, the game really points you into relying on mercenary stacks for the early game. From the start of the game, Carthage can hire 4 mercenary stacks! This is important because your starting levy multiplier is one of the smallest in the game. Their mercenary stacks aren't to be scoffed at either, bringing archers & heavy infantry to battle.

Their mercenary tree leads into getting heavy infantry, elephant, and levy multiplier buffs. So it looks like you should transition into levies in the mid game, especially once you've culturally assimilated most of north africa, as that will let you bring lots of cheap war elephants to battle.

North African Tribes
Your levies will be 40% light cavalry, so it'd be worth investing into the plains bonus then light cavalry tree instead of the Carthaginian mercenary tree. Keep in mind they'll struggle against Heavy Infantry though, so the best strategy to win would be to always engage with a larger stack so the light cavalry can use their manuever bonus.

When fighting North Africans
The classic counter is once again Heavy Infantry and Heavy Cavalry. However the key counter to Carthage is less so the land battles and more so winning on the seas, as the AI will struggle to pour it's full weight anywhere other than Spain or North Africa. When fighting them in their own turf though, it will largely come down to picking your engagements correctly, which means not getting caught out with the wrong tactics.

Trees
Heavy Infantry + Elephant + Mercenary tree
Naval + Levantine traditions tree
Diplomacy + Latin traditions tree
Light Cavalry tree

Culture Groups
Iran:
Archers: 50%
Light Infantry: 10%
Light Cavalry: 10%
Horse Archers: 10%
Heavy Cavalry: 15%

Parthian:
Archers: 50%
Light Cavalry: 15%
Horse Archers: 20%
Heavy Cavalry: 15%

Cadusian:
Archers: 30%
Light Infantry: 30%
Horse Archers: 10%
Heavy Cavalry: 10%

Carmanian:
Archers: 40%
Light Infantry: 40%
Horse Archers: 10%
Chariots: 10%

Persian:
Archers: 30%
Light Infantry: 30%
Light Cavalry: 15%
Heavy Infantry: 10%
Heavy Cavalry: 15%

Caucasian: #Iberia, Kartli & Colchis
Light Infantry: 50%
Archers: 10%
Light Cavalry: 15%
Horse Archers: 5%
Heavy Cavalry: 10%

Albanian:
Light Infantry: 30%
Archers: 30%
Light Cavalry: 15%
Horse Archers: 10%
Heavy Cavalry: 5%

Steppes:
Archers: 40%
Light Infantry: 20%
Light Cavalry: 15%
Horse Archers: 15%
Heavy Cavalry: 10%

Sarmatians:
Archers: 35%
Light Cavalry: 15%
Horse Archers: 35%
Heavy Cavalry: 15%

Scythians
Archers: 45%
Light Cavalry: 15%
Horse Archers: 30%
Heavy Cavalry: 10%

Dahae:
Archers: 25%
Light Infantry: 10%
Light Cavalry: 20%
Horse Archers: 35%
Heavy Cavalry: 20%

Overview
The Persian group has a tendency to bring lots of Heavy Cavalry into the field with Horse Archers on the flanks, as a result their tradition tree has a tonne of buffs in store for them. This means they get some of the strongest heavy cavalry in the game!

To get the most value out of your levies, be sure to have enough citizens and nobles in every region in order to supply more heavy cavalry.

How to counter
Heavy Cavalry in the primary row, Heavy Infantry in the secondary row, Light Cavalry in the Flank.

Military Traditions

Levy Composition
General Arabian:
Light Infantry: 50%
Camels: 20%
Light Cavalry: 20%
Horse Archers: 5%
Heavy Cavalry: 5%

Yemeni:
Light Infantry: 45%
Light Cavalry: 15%
Camels: 15%
Heavy Infantry: 10%
Heavy Cavalry: 10%

Hadramut:
Light Infantry: 45%
Light Cavalry: 15%
Camels: 25%
Heavy Cavalry: 10%

Phoenician
Light Infantry: 30%
Archers: 30%
Light Cavalry: 25%
Heavy Infantry: 15%

Egyptian:
Light Infantry: 50%
Light Cavalry: 20%
Camels: 10%
Heavy Infantry: 20%

Nubian:
Archers: 45%
Light Infantry: 20%
Light Cavalry: 10%
Camels: 10%
Heavy Infantry: 15%

Blemmyan:
Light Infantry: 50%
Camels: 40%
Heavy Infantry: 10%

Axumite:
Light Infantry: 45%
Archers: 20%
Light Cavalry: 20%
Heavy Infantry: 15%

General Overview
Since arid areas have a -40% food malus, Levantine levies tend to be largely be made up of light weight units, including the special Camel Cavalry type. In general, only 10-20% of the levy will be composed of advanced, heavier units. This means Levantine levies tend to be rather fragile.

You can get up to +25% desert combat bonus pretty quickly, giving you a massive bonus if you manage to bait or catch an enemy stack in the desert.

Camel cavalry are decent units and their light weight means they're greatly suited to the desert environments this tree favours. They only take half attrition and pack six more months of food compared to other cavalry. Also they outperform almost all trash units and have easy to access to a 10% discipline buff from both trade goods and the tradition tree. However, they are weak to heavy cavalry, which the Greek successor states will be bringing.

How to counter
Levantine nations are easily countered by the classic Heavy Cavalry + Heavy Infantry combo.
However, the real question is getting your troops to them without having your armies turn to dust.
The desert attrition is brutal, so pay close attention to your armies food supply. It might even be better to stoop to their level and have a core of strong, powerful units and then fill the ranks with Light Infantry.
If your army cant find supply no matter what, one strategy I've found is to move slaves as you go, as each slave provides 0.5 supply.

Military Traditions
Kingdom Traditions (Egypt has access to this despite being in the Greek group)
Camel Combat tree
-Gives +10% discipline and +15% offense & defence for Camels
-Also gives access to North African tree if you've integrated Carthaginian culture
Civic tree
-Gives several national bonuses such as city construction cost, fort defense, city building slots, civilisation level, etc
-Also gives +15% desert combat bonus right at the start
Maritime Traditions
Naval Tree
-Gives several ship buffs
-Unlocks mega-polyremes
Greek Tree
-Gives +10% discipline, +10% moral, +15% offense & defence for Light Infantry
-Also gives +10% discipline, +10% offense and -15% cost for Heavy Infantry
-Gives access to Greek traditions if you've integrated a Greek culture

Culture Groups

• Aryan
  
• Indian
  
• Tibetan

Default AI Unit Compositions
Primary: War Elephants
Second: Heavy Infantry
Flank: Light Cavalry

Favourite Tactics
Shock Action
Padma Vyuha

How to counter
"India is my favourite place to fight" - said nobody
Playing as the Seleucids, these boys will come knocking on your door every so often and it's up to you to tell them to GTFO. Strategy is much more important here than unit compositions, because the indian ai should win most straight up fights. Use terrain and tactics to win. Often I won't bother engaging these guys in direct battle and instead run around them with stacks of cavalry sieging down their provinces. But if you do want to go into a straight up fight, see below.


Heavy Infantry or War Elephants in the Primary Cohort. Buff these units as much as possible.

Heavy Infantry, War Elephants, or Horse Archers in the Secondary Cohort.

Heavy Cavalry on the flank.

Recommended stacks:
2WE-6HI-2HC
8HI-2HC
4HI-4HA-2HC

Military Traditions
Cultural Tradition: Can build Chariots

Left Tree (Tribal Indian Tree)
Archers Offense + 10%
War Elephant Defense + 10%
Light Infantry Morale + 10%
War Elephant Jungle + 15%
War Elephant Forest + 15%
Archers Discipline + 10%
Heavy Infantry Jungle + 15%
Heavy Infantry Forest + 15%
Light Infantry Jungle + 15%
Light Infantry Forest + 15%
Monthly War Exhaustion - 0.01
This tree is great for fighting in India, most of the time. Not so great every where else. Archers in this tree do a lot of damage so probably intended for you to attack and retreat, but I've never really seen that work.

Centre Tree (Diverse Unit & Ship Tree)
Archers Morale + 10%
Morale + 10%
Fort Defense + 10%
Archers Cost - 10%
Chariot Cost - 10%
This tree has multiple ship buffs. The morale buff is also nice as it lets you field a variety of different armies.

Right Tree (Chariots and Mercenaries Tree)
Chariot Defense + 15%
War Elephant Discipline + 10%
Archers Defense + 10%
Padma Vyuha Tactic
Chariot Discipline + 15%
War Elephant Cost - 15%
Mercenary Maintenance - 15%
War Elephant Morale + 10%
This tree clearly expects you to buy lots of mercs and back them up with your own personal chariots. Otherwise it'd be a war elephant, chariot, and archer mix.

Archers
- Usually in the primary cohort
- Very cheap & light weight
- Weak morale, will disengage before taking too much damage
- Useful to weaken enemy infantry before the secondary cohort comes in
- Counter with any cavalry, but especially Heavy Cavalry

Camels
- Usually in the flank
- Expensive, but low weight for a cavalry unit, making it good in low supply areas
- Fast by itself
- Great at flanking when you have a numerical advantage
- Useful if enemy is using Heavy Infantry in the secondary cohort
- Counter with Heavy Cavalry

Chariots
- Usually in the secondary cohort
- Good against Light Infantry and Archers
- Cheap
- If you grab all the buffs for barbarians in the left tree, can be used against Heavy Infantry
- Counter with Heavy Infantry, Heavy Cavalry, Horse Archers or War Elephants

Heavy Cavalry
- Usually in the flank
- Expensive & very heavy
- Weak to attrition
- Fast by itself
- Great against Archers, Light Infantry and other Cavalry
- Okay at flanking when you have a numerical advantage
- Counter with Heavy Infantry or War Elephants

Heavy Infantry
- Usually in the secondary cohort
- Expensive & heavy
- Strong morale, can stay in fights for a long time
- Counter with war elephants, archers, or your own heavy infantry

Horse Archers
- Usually in the flank
- Expensive & heavy
- Very fast by itself
- Weak morale, will disengage before taking too much damage
- Amazing at flanking when you have a numerical advantage
- Counter with any cavalry

Light Cavalry
- Usually in the flank
- Cheap & heavy
- Very fast by itself
- Good at flanking when you have a numerical advantage
- Amazing against Archers, Light Infantry, Horse Archers, and Chariots
- Counter with Heavy Cavalry

Light Infantry
- Usually in the Primary Cohort
- Very cheap & extremely light
- Fantastic morale, with enough morale buffs they will stay in the fight until the last man is dead.
- Use to fill out your combat width so the rest of your army can deal the real damage
- Terrible damage
- Counter with almost anything, but cavalry and elephants work best

War Elephants
- Can be found in almost any cohort
- Rare, only four civs use them.
- Extremely expensive & extremely heavy
- Very weak to attrition
- Takes HALF strength damage (still full morale damage)
- Fantastic against heavy infantry, archers, chariots, and light infantry
- Takes half damage from most cavalry
- Counter with better morale

Cohort = Any sort of military unit you can move around the map in armies
Army = Collection of cohorts. Every cohort belongs to an army, and every army has at least one cohort.
Morale = How long a cohort will fight before retreating. Cohorts with damaged morale will deal proportionately less damage.
Strength = How many men are fighting fit in a cohort. Full strength is always 1000 men. Cohorts with less strength will deal proportionately less damage.
Damage = When a cohort attacks, it reduces the enemies morale and strength until the enemy cohort either retreats or is destroyed.
[Unit Type] Discipline = A country modifier that increases how much damage a cohort deals, while reducing how much damage they take.
[Unit Type] Offense = A country modifier that increases how much damage a cohort deals. Stacks with discipline.
[Unit Type] Defense = A country modifier that decreases how much damage a cohort receives. Stacks with discipline and cohort experience.
Cohort Experience = A modifier that decreases how much damage a cohort receives. Stacks with discipline and defense ability. The amount of experience a cohort has is determined by how much combat they've seen or how much drilling they've done.
[Unit Type] Jungle/Forest/Desert/Hills/Etc = A modifier that gives bonus damage depending on where the battle takes place.
Fort Defense = Increases the amount of time between siege phases, increasing how long it takes to siege.
Siege Ability = Decreases the amount of time between siege phases, decreasing how long it takes to siege.
Siege Dice = Gives you better odds to roll a favourable outcome during a siege, decreasing how long it takes to siege.
[Unit Type] Maintenance = A modifier that changes the maintenance of a cohort. Stacks with [Unit Type] cost.
[Unit Type] Recruitment cost = A modifier that changes how much it costs to make a new cohort of that type. Stacks with [Unit Type] cost.
[Unit Type] Cost = A modifier that changes both the maintenance and recruitment cost of a cohort. Stacks with [Unit Type] maintenance and [Unit Type] recruitment cost.
Attrition = A modifier to how much attrition your army takes. Most territories have a base attrition of 5% of your armies strength a month if you exceed the territories weight. So a -15% attrition modifier will reduce that 5% base to 4.25%
Manpower = A country modifier that changes how much manpower you can have stored, and how quickly it recovers.
Manpower Recovery = A modifier that affects how quickly you regain manpower.

Most of this guide was written while playing on Very Hard, where the AI will send monstrous hordes of units at you. So as a result most of the compositions here are based on constant and intense fights. The compositions start to struggle on the strategic level if you don't have the resources to pour into them. If you're fighting deep into low supply territory, swap most of the compositions out for light infantry and you should be fine.

Light infantry are great for stalling fights so your main force can arrive and deal damage.

If you have any questions, please feel free to leave them below or message me directly. Thanks for reading my guide.

20/10/2019 - updated for 1.2
26/10/2019 - updated counters