Here is the full list of all 10 iso-Sphere achievements.
Get time badges for all bonus levels in world 4.
Collect all time badges on all main levels.
Complete all levels in World 4.
Collect all stars across all four worlds.
Get time badges for all bonus levels in world 3.
Complete all levels in World 3.
Get time badges for all bonus levels in world 2.
Complete all levels in World 2.
Get time badges for all bonus levels in world 1.
Complete all levels in World 1.