Here is the full list of all 22 ChromaGun achievements.
Grill 100 WorkerDroids on Deadly Maintenance Tiles.
Finish Chapter 8.
Find the hidden cake we actually have, as opposed to that other game that doesn't have a cake.
Finish Chapter 7.
Finish Chapter 6.
Finish Chapter 5.
Rescue the WorkerDroid in Chamber 5-2.
Finish Chapter 4.
Finish Chapter 3.
Simply walk onto the Deadly Electrified Maintenance tile in Chamber 3-1.
Grill a WorkerDroid on a Deadly Electrified Maintenance Tile.
Solve a chamber in chapter 7 without firing a single shot.
Try jumping over a Deadly Electrified Maintenance Tile... and fail horribly.
Mix a color. It's not that hard, really.
Try painting a brown WokerDroid and realize how pointless that was.
Open a door by activating a trigger.
Fire 100 shots.
Finish Chapter 1.
Finish Chapter 2.
Get killed by a WorkerDroid.
Try jumping... and fail.
Shoot a WorkerDroid.