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.
Beat the “Frozen Mines” level.
Obtained all shards.
Found the Silver Claymore
Beat the “Aqueducts Area 2” level.
Opened all level paths.
Found the Dark Armor.
Reach the final level blocked path.
Beat the “Devil’s Peak” level.
Obtained all relics.
Found the Steel Claymore.
Beat the “Underground Temple” level.
Beat the “Aqueducts” level.
Found the Combat Armor.
Beat the “Dark Forest Area 2” level.
Play a game session for 2 hours.
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.
Found all Heart Pieces.
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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".