Here is the full list of all 23 Paper Planet achievements.
Beat the game and perfect every zone.
Have over 10,000 active bullets on screen at once.
Use every item in Boss Rush.
Beat Boss Rush without firing a single bullet (except selector bullets).
Play co-op with a friend or two or ten.
Beat the game without losing combo.
Beat the game with all spices enabled at their maximum level.
Reach 2,500 combo.
Take 15 or more damage in a single run.
Have 20 or more Rat Buddies on your planet at once in creative mode.
Beat the game or boss rush without getting hit.
Beat the game with only 1 item picked up.
Purchase all items in a shop during a run.
Beat a normal run in 12 minutes or less.
Beat the game with maximum spice, without getting hit or losing combo, in 18 minutes or less. Phew!
Unlock and pick up all items, gamemodes, planets, and library entries..
Defeat Sharp for the first time.
Defeat the twins Phobos and Deimos for the first time.
Defeat the Wildfire for the first time.
Defeat the overgrown flower, Violet, for the first time.
Defeat the space wizard Zenith for the first time.
Defeat Zenith in under 5 seconds - so mean!
Defeat the starworm Karmai for the first time.