Here is the full list of all 32 Deadlings: Rotten Edition achievements.
Complete all bonus levels with maximum rank.
Complete all bonus levels.
Complete bonus level 10.
Complete all levels in Nightmare Mode with maximum rank.
Complete 60 levels in Nightmare Mode.
Complete 45 levels in Nightmare Mode.
Complete 20 levels in Nightmare Mode.
Collect 200 stars.
Complete phase 4.
Complete all levels in Normal Mode with maximum rank.
Discover a crazy mutators.
Collect 150 stars.
Complete phase 3.
Discover a freezing freezers.
Discover an awesome portals!
Collect 100 stars.
Complete phase 2.
Finish 20 levels without killing a single zombie.
Collect 50 stars.
Discover a deadly lasers.
Unlock the Lazybrain.
Complete level 14 in less than 10 seconds.
Complete phase 1.
Kill the zombie with the other zombie.
Complete level 04 using one zombie.
Collect 800 brains.
Unlock the Gasfat.
Collect 400 brains.
Kill over 100 zombies.
Complete 5 levels in Nightmare Mode.
Collect 150 brains.
Unlock the Creep.