Here is the full list of all 34 Zombie Night Terror achievements.
Assemble a horde of 12 zombies with a screaming Overlord
Lose a level by sacrificing your last zombie
Kill 50 cops
Start the level editor
Bite 1,337 humans to death
Defeat the Boss in Chapter 3
Paint over 9,000 blocks with blood
Kill 7 enemies with a single Tank dash
Defeat the Boss in Chapter 2
Blow up 4 humans with a single explosion
Prevent a zombie from falling to its death by blowing up another zombie
Scare 6 humans with a single scream
Kill Gronald
Collect 100 Mutation Barrels
Let 1,000 zombies die
Defeat the Boss in Chapter 1
Let 66 zombies fall to their death
Collect 1,000 DNA units
Kill a zombie by making him jump from too high
Fall with style for at least 10 seconds with a zombie
Blast through 256 breakable blocks
Kill a zombie by blowing up another zombie nearby
Destroy 28 doors
Bite 10 humans to death in 15 seconds
Use 5 contaminations on humans
Kill 10,000 humans
Defeat the Boss in Chapter 4
Spend 104 minutes on the Credits page
Let a Tank get squashed
Be patient!
¯\_(ツ)_/¯
Successfully complete all levels
Successfully complete all challenges
Create a level and upload it to Steam Workshop