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