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