From Emil Chronicle Wiki

Arcana Heart is a level 38 monster.

[edit] Stats

Basic	Combat
Level 38 Experience 450 Job Experience 250 HP 420 SP 110 MP 255 Behavior  ???	Type Magic Creature A.SPD 0.00 ATK 85 - 100 DEF 120 C.SPD 4.00 M.ATK 270 - 350 M.DEF 100
Properties Light(30%) Item Drops Paper, Heal Potion, Ancient Book, Old Book, Arcana Heart Stamp Skills  ??? Location Northern Dungeon