Finish the first chapter
Place an object on top of another
Prevent a moving platform from reaching its destination
Finish the second chapter
Finish the third chapter
Send a laser to a different world
Finish level 3.1: At Last with a single horizontal movement
Finish level 2.6: Watch your Head without jumping
Finish level 2.4: John's Drop by toggling a lever only once
Finish level 3.16: Stasis without moving sideways
Finish level 3.10: Secret Passage in 10 seconds or less