Here is the full list of all 34 Zombie Night Terror achievements.
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Spend 104 minutes on the Credits page
Kill 10,000 humans
Be patient!
Bite 1,337 humans to death
Defeat the Boss in Chapter 4
Successfully complete all levels
Successfully complete all challenges
Start the level editor
Let a Tank get squashed
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
Collect 100 Mutation Barrels
Assemble a horde of 12 zombies with a screaming Overlord
Kill 50 cops
Let 1,000 zombies die
Scare 6 humans with a single scream
Blast through 256 breakable blocks
Kill Gronald
Blow up 4 humans with a single explosion
Defeat the Boss in Chapter 1
Prevent a zombie from falling to its death by blowing up another zombie
Let 66 zombies fall to their death
Kill a zombie by blowing up another zombie nearby
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
Destroy 28 doors
Use 5 contaminations on humans
Bite 10 humans to death in 15 seconds
Lose a level by sacrificing your last zombie
Create a level and upload it to Steam Workshop