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