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