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