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