From Granblue Fantasy Wiki
|Character UnlockObtaining this weapon unlocks a character.
Drawing additional copies beyond the first will instead earn a Gold Moon.
|4★||Complete Ferry (Grand) Lvl 45 Fate Episode "The Last See-You-Again"|
|Its otherworldly melody is known to invite calamity. Those enticed by the sweet siren call of this harp have their souls plunged into the depths of the underworld, where they must wander the boundless darkness for all eternity.|
|Corposant||Massive Dark damage to a foe.
Dark allies gain .
Additional effect at 4★:
Dark allies also gain 
|Oblivion's Sentence||Big boost to dark allies' C.A. DMG and C.A. DMG cap|
|▼ 120||Upgraded at level 120 to:||Upgraded at level 120 to:|
|Oblivion's Glory||Big boost to dark allies' C.A. specs and chain burst specs|
|150||Unlocks at level 150:||Unlocks at level 150:|
|Hatred's Grace||Medium boost to dark allies' max HP and debuff resistance|
- Gamewith, Unheil https://グランブルーファンタジー.gamewith.jp/article/show/143931