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