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