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