Here is the full list of all 63 ATONE: Heart of the Elder Tree achievements.
Get a 90% hit rate on any Arena battle.
Fight your first Arena battle.
It's over. You can go home now.
Battle Freya.
Solve The Unsolvable Puzzle.
Solve Gulli's Puzzle.
Solve the Stumped to Death puzzle.
Solve the grouped puzzle.
Battle Loki.
Battle the Ice King.
Aid Blue Heart in her task.
Battle Skullhorn.
Read 20 Story Nodes or Books.
Solve the Who Sits Where? puzzle.
Solve the Griddled puzzle.
Solve the Stumped Again puzzle.
Find the famous tiny shield
Save Forsetti from her fate.
Battle Heldi.
Solve the Jumbled Freedom puzzle.
Solve the How Many? puzzle.
Solve the Water Runes puzzle.
Solve the Blockad puzzle.
Solve the Stumped puzzle.
Battle Viktor.
Battle Jörm.
Solve the Jumbled Divide puzzle.
Solve the Bloodtrack Puzzle.
Solve the Grid puzzle.
Talk Sven from his Blue Vein state.
Battle Sven.
Protect the Elder Tree.
Train with Thyon.
Help Dallr tune his lute.
Buldr and Forsetti come to Yri's aid.
Set Eiryn on her own path.
Sometimes sacrifice is necessary to save the world.
Goodbye little friend.
This is the end.
Collect all the Magic Mead ingredients.
Drink the Magic Mead.
Obtain Mayweed from Sven.
Find a small peice of Odin's spear
Return Eiryn's knife to its rightful owner.
Answer all of Vèldin's questions correctly.
Complete all of Isa's puzzles.
Solve the Tracked puzzle.
Solve the Spring puzzle.
Unlock 13 Battles.
Battle Old Man Wulf.
Battle Buldr.
Battle Hati and Skol.
Obtain Odin's Ring from Jörm.
Obtain Jörm's venom.
Battle Taangrisnir.
Carry 1250 coins.
Score 6500 points against Odin.
Score 6500 points against Dallr.
Get a 90% hit rate against Tanngrisnir in Arena.
Score more than 10,000 points on any battle.
Get a 90% hit rate on at least 5 arena battles.
Get a 90% hit rate on at least 10 arena battles.
Get a 90% hit rate on at least 15 arena battles.