Full list of all 53 Fell Seal: Arbiter's Mark achievements.
The base game contains 43 achievements, and there is 1 DLC pack containing 10 achievements.
Cleanse the Cursed Shield
Get the second ending
Master all 19 base Monster Classes
Open all treasure chests
Complete the Obelisk riddle
Master all Human story character Classes
Defeat Morgaine
Recruit Kairu
Unlock the Spymaster Class
View all optional dialogue events
Defeat Lady Anquine
Get the first ending
Complete the Ancient Path
Open 50% of treasure chests
Master all 6 special badge Classes
Craft a final-tier weapon
Save Somier a second time
Win the second Tournament
Defeat at least 4 enemies with a single hit
Visit the fifth Relic
Master all 20 base Human Classes
Visit the fourth Relic
Complete the Halloween encounter
Unlock all 20 base Human Classes
Obtain all gadgets
Recruit Katja
Visit the third Relic
Drown an enemy
Defeat an enemy with falling damage
Win the first Tournament
Recruit Bzaro
Use your first Class badge
Defeat an enemy with a Berserk, Charmed, or Mind-Controlled enemy
Visit the second Relic
Unlock the Demon Knight Class
Recruit Yates
Master any Class
Craft your first item
Visit the first Relic
Unlock the Marked Class
Defeat an enemy by using a Counter Ability or Thorns
Defeat a unit with its Elemental weakness
Change Class at least once
Master all 22 Monster Variants.
Complete an encounter deploying only Monsters.
Enlist each of the base 18 recruitable Monster types.
Defeat an enemy with a Pet Effect.
Complete all unique Hunts and large-scale battles.
Complete all Missions.
Master the 3 new Human Classes.
Fully upgrade all 5 regions.
Complete 100% of Missions in one region.
Build a Guild Upgrade.