Great Old One

Great Old One (旧支配者,) is a non-ability that activates Howard Phillips Lovecraft's eldritch form.

Description
Great Old One allows Lovecraft to transform either a part or his whole body into an eldritch monster with tentacles. As such, he can contort his body parts, and his eyes notably become wider and almost blank. He can also sprout numerous tentacles dotted with suction cups and holes along their surface at random intervals, is undefined in length, and anywhere from his body.

Lovecraft's true form appears as a massive, tentacled entity with wings and a pair of glowing, seeming eyes. In this state, he is only vulnerable from the inside. Since this power is not an ability, Osamu Dazai is unable to nullify it.

Traits

 * Mental Immunity: Lovecraft is immune to most, if not all, mental-based abilities.
 * Enhanced Durability: Lovecraft can survive injuries and wound causes that would be instantly lethal to a normal human, including but are not limited to dislocation, skeleton fracture, and point-blank explosions.
 * Healing Factor: Lovecraft can heal from wounds that are considerably lethal to an average human.
 * Regeneration: Lovecraft can regenerate his limbs even after a powerful attack. To note, he can almost instantly regenerate while in his true form.

Appearances
{{Ability Appearance
 * Chapters =

The Guild Arc

 * Chapter 23 - The Grapes of Wrath Ripen in His Eyes, Part 1
 * Chapter 24 - The Grapes of Wrath Ripen in His Eyes, Part 2
 * Chapter 27 - Upon the Shattering Shores
 * Chapter 31 - The Twin Darkness
 * -|Episodes =

The Guild Arc
}}
 * Episode 19 - Will of Tycoon
 * Episode 20 - Though the Mind May Be Wrong
 * Episode 21 - Double Black

Derivation
The ability is a reference to Great Old Ones, a group of horrific extra-terrestrial beings in H. P. Lovecraft's classic short story, The Call of Cthulhu.