Here is the full list of all 14 Loopindex achievements.
Solve a level with mice.
Defeat the boss.
complete the pre-boss level.
Use the blue arrows to complete a level.
Complete the first level with treadmills.
Use the teleporter to complete the level.
Complete your first level with an iman crane.
Successfully overcome the first shooters.
Complete a level using a bomb.
Complete level 16.
Solve a level with robofrogs.
Cross the river and complete the level.
Use the red directional floor arrows to complete a level.
Solve a level with a box.