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