Here is the full list of all 42 Bullshot achievements.
Kill 1000 cardesians
Find the collectables in the bio technology lab.
Finish the bio technology lab stage.
Finish the Oil Fields stage.
Find the collectables in the oil fields.
Find the collectables in the desert
Finish the heart in the bloodiest way
Watch the credits.
Find the reader in the sewers
Destroy the van from above
Find the reader in the prison
All that glitters...
Destroy the heart of the giant worm
Finish the desert stage
Find the reader in the desert
Finish the biker stage
Finish the sewers stage
Find the collectables in the sewers
Break the car in the bonus stage
Escape from the prison
Find the collectables in the prison
Finish a non-bonus stage without jumping
Finish a stage with full health
Free all B.O.A. in the prison
Kill 100 cardesians
Charge 100 enemies in one game.
Kill 10 cardesians
Change the settings of the TV filter.