Here is the full list of all 45 Children of Morta achievements. It takes around 25-30 hours to unlock all of the achievements on Windows.
Defeat OU.
Free Anai-Sarava.
Have 20000 Morv.
Find 10 divine items in a single dungeon.
Free the blackmarketeer.
Bring Hope into the world.
Upgrade 25 times in the workshop.
Upgrade The Book of Rea 5 times.
Complete 5 in-run events.
Shelter the stargazer.
Free Anai-Raha.
Kill 5000 enemies.
Unlock all playable characters.
Rescue Mary.
Kill 50 ferocious enemies.
Unlock a family trait of three different Bergsons.
Free Anai-Dya.
Save the wolf cub.
Have 3 runes equipped simultaneously.
Upgrade 10 times in the workshop.
Use 5 charms in the same dungeon run.
Gain each obelisk effect at least once.
Defeat the Spider King.
Free the shopkeeper.
Unlock a family trait.
Investigate the shrine of Rea.
Reunite the automata.
Construct Ben's wine machine.
Complete 10 in-run events.
Free the runemender.
Upgrade 75 times in the workshop.
Upgrade The Book of Rea 15 times.
Unlock all family traits of a Bergson.
Unlock all family traits.
Bring back 15 souvenirs from the dungeons.
Find 20 journals.
Resolve 20 puzzle events.
Complete 10 challenge rooms.
Kill 100 enemies using hazards.
Kill 250 ferocious enemies.
Finish a dungeon in co-op mode.
Revive 5 times in co-op mode.
Find 10 secrets.
Kill a boss with every playable character.
Kill a boss without receiving damage.