TV-Series
Description
Cocytus serves as the Fifth Floor Guardian of the Great Tomb of Nazarick, crafted by the Supreme Being Warrior Takemikazuchi. He manifests as a 2.5-meter-tall insectoid humanoid, combining features of a mantis and an ant. His imposing form bears four arms, a tail twice his height, and sharp icicle-like spikes covering his body. A constant chill emanates from his pale blue exoskeleton, which functions as natural armor releasing diamond-like dust. This exoskeleton grants inherent frost resistance and fire resistance, though it is less durable than divine-level equipment. He typically wields multiple weapons simultaneously: a silver halberd, a black-light mace, and the katana God Slaying Emperor Blade.

Embodying a warrior's ethos, Cocytus respects opponents demonstrating strong fighting spirit, honoring worthy adversaries by preserving their weapons or corpses as trophies. His loyalty to Ainz Ooal Gown is unwavering, though initially manifesting as blind obedience. His first campaign's failure against the lizardmen plunged him into profound self-doubt, driving him to prepare for ritual suicide to atone. This defeat became a pivotal turning point, prompting deeper reflection on independent decision-making and strategic adaptation. He evolved into a more outspoken advisor, emphasizing rational choices during conflicts and carefully considering Ainz's directives before execution.

As Nazarick's designated weapon master, Cocytus possesses mastery over 21 distinct weapons and wields the greatest physical attack power among the Guardians when armed. His combat capabilities include cryokinetic skills like Frost Breath and Ice Pillar, alongside area-effect attacks such as Acalanatha (a wind slash) and Acala's Sword. Passive abilities encompass a continuous Frost Aura dealing ice damage within a 100-meter radius and an unnamed skill nullifying weakly enchanted weapons. He also carries an unnamed World Item for protection against other World Item effects. Following Nazarick's transition to the Sorcerer Kingdom, he assumed command of its military forces, training undead, demi-humans, and human soldiers. He also administers the lizardmen village, instructing its inhabitants in combat and Nazarick's protocols, fostering mutual respect.

Cocytus desires to spar with formidable warriors like Sebas Tian and Ainz, aspiring to train Ainz's potential heir. He expresses concern over Nazarick's future stability without an heir, fearing internal discord. His relationships with other Guardians are complex; he considers Demiurge both a rival and a friend, while his combat capabilities are contextually superior to Albedo's but inferior to Sebas's within their tactical triangle. Despite personal envy toward fellow Guardians, he prioritizes Nazarick's collective honor above individual pride.