Here is the full list of all 24 Pressure Overdrive achievements.
Finished the campaign on Hard difficulty.
Got in love touch with 10 enemies.
Finished a level without taking any damage.
Finished a level with a buggy at maxed-out pressure capacity.
Defeated 100 enemies through ramming.
Finished the campaign on Normal difficulty.
Finished 10 Hornets with the railgun without missing once.
Had a Spatank drag the buggy with a grappling hook for 30 seconds.
Finished a level with having activated underbody or rear explosives for 20 times.
Defeated 18 enemies while a powerup was active.
Defeated the Underground Boss in Level 33.
Finished the campaign on Easy difficulty.
Finished 20 levels in Endless mode.
Defeated the Castle Boss in Level 22.
Let a Sucker suck at least 10 pressure pills before destroying it.
Finished a level with the buggy at maxed-out hull.
Finished a level with a fully upgraded Teslagun and Tesla secondary.
Defeated 5 enemies with one strike.
Defeat the Riverbed Boss in Level 11.
Defeated 1000 enemies.
Defeated all enemies in a level (Tutorial excluded).
Brought 5 love-touched enemies to the finish line.
Didn't touch the ground for 15 seconds.
Finish a level without driving on 'low pressure'.