Before we get started, I'd like to say that this guide is my first attempt at a full 100% achievement guide, as such it will be barebones (no images, no videos) and may have a few errors, so if i've gotten anything wrong, please let me know in the comments.
Let's get to it shall we?

This guide splits up the achievements into different categories to make it easier to follow. There is 8 level related achievements, 7 kill related achievements, 2 perk and 4 gun related achievements, 4 PVP related achievements and 10 Misc achievements. 35 total achievements.

Escape
Finish episode "New York" on any difficulty
Self explanatory, just complete the New York level and you've got an achievement. You can do this on any difficulty.



Hope
Finish episode "Jerusalem" on any difficulty
Self explanatory, just complete the Jerusalem level and you've got an achievement. You can do this on any difficulty.



Salvation of the Motherland
Finish episode "Moscow" on any difficulty
Self explanatory, just complete the Moscow level and you've got an achievement. You can do this on any difficulty.



This is just the beginning
Finish all episodes on any difficulty
For this, you only need to do the first 3 episodes, which is "New York", "Jerusalem" and "Moscow". Simply because all the other episodes were added at other times when the game was out.



Well, what did you achieve?
Finish all episodes on hardest difficulty
Self explanatory, complete every level, on the hardest difficulty, which is set to the Extreme difficulty.



Madman
Finish 100 games in PvE
Complete 100 games against bots. Just play the campaign levels over and over again, nothing too hard.



Strong immunity
Finish any level without using health packs
Easier than it sounds. Just complete the round without using your health packs.



Teamwork
Finish any level with full team
Finish the level, with every member of your team surviving (including bots).

The floor is lava
Burn 10 zombies with one gasoline puddle
Throughout the levels you'll come across a few red barrels with a gasoline puddle near it. When there's a swarm of zombies heading in the direction of that barrel, shoot it or the gasoline, and you should get it, if enough of them run through it and catch on fire.



Chain reaction
Hit 10 zombies with one tazer shot
Using the Slasher class and a stun gun, try and hit 10 different zombies with one tazer shot. You will need to upgrade the class a bit, as attempting it with no upgrades is damned near impossible. At least for me anyway.



Explosive
Kill 10 zombies with balloon explosions
You can find some explosive red canisters around during the levels, shoot them when an enemy or two is near it. After a few kills via this method, you'll get the achievement.



Can't fool me
Kill 20 lying zombies before they get up
Some zombies will be playing "dead", usually when you enter a new area. You can see they're still sort of "alive" if you hold your cross-hair over them and it turns red. Shoot them, kill them, bam you got another achievement.



Torero
Kill Bull during charge
You can find a few tanky looking zombies throughout the levels, that are similar to the Left 4 Dead Chargers, in which they'll charge at you and if they get their hands on you, will start pummelling your very essence into the ground.
You need to kill them whilst they're charging to get the achievement.



Sport kills
Kill Lurker midair
Another zombie that reminds me of an enemy from Left 4 Dead is the Lurker. A lot like the Hunter, it usually hides in the dark and jumps on you, holding you on the ground and throwing a few punches here and there.
You need to kill him whilst it's trying to jump on you (might be obtainable if it was trying to jump on a team mate).



Genocide
Kill 10,000 zombies
Looks like a drag, but is actually easy. It should be obtained once you complete like 4 or 5 of the campaign modes and you've done quite a lot of killing in each of them.

There are many guns but this one is mine
Open and buy final version of any weapon
So, before playing a round, you can customise which weapons you start with and the ones you will be able to pick up during said rounds. Purchase each version of, lets say, the 1911 Protector Pistol, all the way up to the final version. Boom, you got that achievement.



Imposing arsenal
Open and buy final versions of all weapons
Just like the last one, but instead of just the 1911 Protector Pistol, you're going to want to do it with every single gun in the game.



The most effective way
Finish any level using just pistol
Pretty simple, but rather difficult. Play an entire level, without using any other weapon, but your pistol to kill. (You can use your melee and equipment like grenades, but not sure on defences like the manned machine gun).



High caution
Finish any level without dealing friendly damage
Complete an entire level, without hurting your teammates in any way. This is done best with friends or skilled players, on a voice chat.

Specialist
Open and buy all perks in one specialisation
Similar to the gun perks, you can choose what class you go with. For example, I use Gunslinger, so the logical step for this achievement is to buy all the perks in the Gunslinger tree. For you, it could be the Medic tree or Vanguard tree or one of the other many perk choices.
Note: You don't have to prestige it, buying all the base perks alone will count towards the achievement.


Handyman
Open and buy all perks in game
Well, do the one above again but for all of the perks in the game. May take some time, as it involves getting to level 30 with each class.
Note: This also includes getting all Multiplayer classes to 13.

Veteran
Finish 25 PvP matches in any mode
Play 25 different Multiplayer matches to the end. You don't have to win, just participate.



Winner in life
Finish PvP match with highest score in any mode
Get the highest score on the winning team.



Owner
Capture the point and hold it until the end of match
In "Domination", capture and keep hold of the point without letting the enemy team take it.



Walking bank
Gather 200 resources during single match in scavenge raid mode
Just collect as many boxes as you can, whilst also avoiding death as much as possible. Once you've got 200, you should get the achievement. If it doesn't pop immediately, it should by the end of the match.

Waste of time
Defuse 10 mines
Sometimes, you'll come across some claymores. Watch where you step around with them, if you step in front of the red lines, they go boom (obviously). Slowly approach from behind, until given the option to defuse.


Friend of machines
Capture 15 turrets
Sometimes you can come across hostile turrets. Good news though, they can be reprogrammed to attack only the evil dead, and not you.


Burglar
Open 15 rooms or containers with a breaching charge
Breaching charges can be a pain to find, but once found, can be used to open up some doors that can't be opened without them. Just open 15 of these doors and voila, you have another achievement.


Builder
Build 100 defences
When preparing to defend against a swarm of zombies, there will be items like barbed wire and auto turrets that you can place around. Simply place 100 of these items and you should get the achievement.


Toxicomaniac
Walk into toxic cloud 100 times
Most times upon death, the "Gasbag" enemy will leak a toxic cloud. Walk into these toxic clouds 100 times to get the achievement.


Effective communication
Mark special zombies 50 times
If you see a special type of zombie, press T to mark it out. Do this 50 times and you get the achievement.


Dispenser
Dispense 10 explosive ammo packs to teammates
Using the "Fixer" class, you will have supply bags which have explosive ammo in them, which your teammates can use. Just deploy them, and you should get the achievement.


I am safe!
Use masking grenade on 3 teammates with zombies near
You can obtain masking grenades via a specific perk in the "Fixer" class. Just use one on your teammates when surrounded by zombies.


First Aid
Rescue 30 incapacitated teammates
Help downed teammates up on 30 different occasions. Can be done with bots.


What the doctor ordered
Heal 30 teammates with health lower than 20% with health packs or stim pistol
Just wait until your teammates are critically injured and then heal them. Do it 30 times and boom, achievement. Can be done with bots.

That's it folks, thanks for checking out this guide, hope it helps and good luck too all hunters and completionists out there. If you have any questions, drop a comment and i'll do my best to answer it.

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