Here is the full list of all 10 Negative World achievements.
Complete all the World 1 Levels
Complete all the World 2 Levels
Complete all the World 3 Levels
Complete all the World 4 Levels
Complete all the World 1 Inverse Levels
Complete all the World 2 Inverse Levels
Complete all the World 3 Inverse Levels
Complete all the World 4 Inverse Levels
Complete a regular playthrough of the game
Complete a level without jumping