Here is the full list of all 29 Odallus: The Dark Call achievements.
Beat the entire game only using Hunting Clothes.
Beat the entire game only using Haggis' Sword.
Completed the game.
Completed 100% of the game in normal mode.
Obtained 10.000 orbs (total) in a single game.
Spend 6.000 total orbs on the merchant.
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Beat the “Frozen Mines” level.
Obtained all shards.
Found all Heart Pieces.
Found all Weapon Bags.
Found the Dark Armor.
Opened all level paths.
Reach the final level blocked path.
Beat the “Devil’s Peak” level.
Beat the “Aqueducts Area 2” level.
Found the Silver Claymore
Beat the “Underground Temple” level.
Obtained all relics.
Found the Combat Armor.
Beat the “Dark Forest Area 2” level.
Found the Steel Claymore.
Play a game session for 2 hours.
Beat the “Aqueducts” level.
Beat the “Dark Forest” level.
Beat the “Town” level.
Completed the game in less than 2 hours.
Completed the game in "Veteran Mode".
Completed 100% of the game in "Veteran Mode".