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