Here is the full list of all 12 Alter World achievements.
Jump! Jump! Jump!...and again Jump!
Brave enough? die 100 times!
Complete 20 Levels
Complete 10 Levels
Forever gone to Alter!
Meet developer!
Complete 30 Levels
Complete 40 Levels
Complete 50 Levels
finish game with first ending
Finish game with second ending
last death!