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