Here is the full list of all 40 DROS achievements.
Drank a can of prima rush
Sing the Splitting of the Spirit with Chester in Pipes
Found the hidden Dros refuge
Drank a can of prima gaze
Got captain's arm back!
Broke the seal of Earth!
Broke the seal of Fire!
Broke the seal of Water!
Broke the seal of Air!
Drank a can of prima jolt
Drank a can of prima blitz
Drank a can of prima blue
Heard the wisdom of the earth moderat
Heard the wisdom of the fire moderat
Heard the wisdom of the water moderat
Heard the wisdom of the air moderat
Caught the clam in under 1 minute
Helped Fisherman catch the 4-eyed cod
Became an honorary Dros League of Resistance member
Exchanged a designer shell for Marvin's ticket
Released the prisoners from the Oubliette
Send the Monk broke in Pochinko Parlour
Collected the Flute
Spoke to Zloff about the Drognaughts
Posed for Madam Bouvine
Exchanged the fearsome Pirate Flag for plunder
Chatted to Jed in his padded Hut
Drank a Soggy Bottom Blop
Stumbled across abandoned Bounty Hunter Armour
Defeat Cronenbergs army in Rejects
Patience is a virtue...
Beat the game
100%