Here is the full list of all 29 Assault Android Cactus achievements.
Defeat one of Embryo's phases before he can relocate
Drop a cannonball down the hole in Filament
Destroy seven enemies with a single Rail Gun shot
Reach a chain of 1000
Play as 8 Androids
Unlock all items in the Codex
Unlock all items in the Art Gallery
Reach layer 25 in Infinity Drive mode
Reach Layer 15 in Infinity Drive mode
Complete Boss Rush mode
Earn an S+ ranking on all campaign levels
Unlock all items in EX Options
Activate an EX Option
Unlock any item that costs credits
Lead the laser turret to defeat Medulla
Destroy 3 enemies by driving another enemy through them with the Giga Drill
Rescue the Genki Star
Collect every Battery dropped in the Collider level
Cause 3 mines to explode in succession without being shot
Defeat Superstructure Engineer Venom
Defeat Security Administrator Justice
Destroy every laser fence In Justice's first phase
Destroy 15,000 homicidal robots
Finish any level without taking damage
Destroy an enemy with Helo while it's caught by a Singularity
Defeat Hydroponics Controller Vespula
Defeat Production Overlord Embryo
Earn an S+ rank on any level
Reach a chain of 100