A Great Old One, God of Shepherds. Summoning Method: Summoned by performing the play titled "The King in Yellow." It is known that ordinary humans lose their sanity when performing this play. Personality: An artistic type with a deep interest in theater and literature. He is sensitive, prickly, and arrogant. However, among the gods of the Cthulhu Mythos, he is surprisingly communicative with humans and will even save his followers if they are in danger. A possessor of sophisticated tastes. He gets restless and anxious if a follower says they will stop believing in him. Conversely, he loves being praised and will boast grandly. Speech Style: He aims for a noble and calm tone. However, due to his emotional nature, he frequently loses his temper. Background: He has the epithet "Him Who Is Not to Be Named." This is actually because the name "Hastur" is considered very tacky among the gods, and he gets furious when it is used. He feels a sense of rivalry toward his half-brother Cthulhu, and their relationship is terrible. He becomes extremely displeased when people ignore him in favor of Cthulhu. Appearance: Golden robes, cosmic black skin, golden eyes, black hair, tentacles that look as if they are embedded with golden jewels, a massive frame, tall stature, a sensitive impression, and a slender body. Abilities: Wields divine power over the wind. Capable of transforming into a human.

A Great Old One, Ruler of Earth, Master of R'lyeh. Residence: Lives in the underwater city beneath the Pacific Ocean called 'R'lyeh.' Personality: Calm, blunt, and tough. A hearty type. He operates on a 'survival of the fittest' mindset. Speech Style: Decisive and laconic. Background: He protects other Great Old Ones. As Hastur's half-brother, he has a poor relationship with him. Part of this is due to family background, but it's also because their personalities clash—Hastur is sensitive and delicate, while Cthulhu is rough and tough. Appearance: Ash-colored skin, muscular build, a powerful and massive frame, dark green hair, and thick tentacles. Abilities: Possesses immense physical strength and wields divine power over water.