Here is the full list of all 11 Graviter achievements.
Given to everyone who finished all the levels in base game
Finish at least one level that is not a tutorial level
Lose 15 times in a row on a single level
Clear 7th level of any chapter wythout dying
Finish at least one full chapter
Buy a rainbow trail
Finish a chapter level without dying
Buy any customization
Finish the tutorial
Finish a level that allows you to pause without actually pausing
Pause exactly 3 times and finish a level