Here is the full list of all 27 One by One achievements.
Have 3 weapons reload at the same time
Defeat the crusher of worlds
Steal Devil's time. He has no time for games
SPEEDRUN! Complete the game with one life.
Face defeat in the dungeon
Defeat the Empress.
Survive dry room, where fires spread faster!
Find lost scroll
Defeat rare enemy
Find this artifact in the darkest corners of the jungles
Reveal all rooms in labyrinth
Complete the game in Hardcore difficulty
Survive crystal infused room
Complete labyrinth in 90 seconds
Complete the game from start without picking any artifacts
Defeat the Desperation.
Acquire 3 equipment in one run
Survive AI court
Defeat the Guardian without picking any item (Low%)
Become a monster. Long stay at Arena of Desperation has a bad influence on health.
Avoid any damage at AI court. Nailed it!
Encounter parasites in caves. Maybe, we can pet them?
Defeat the Guardian
Witness fires consume whole room
Thriumph over harpy queen
Snipe down a monster from far off
Resque this adventurer in the Uncertainty