Hades is the King of the Underworld and primary antagonist, leading his army in a cyclical war against Athena for Earth's dominion. His soul reincarnates every 243 years, requiring a pure human host to inhabit, thus shielding his true divine form. Notable hosts include a figure from Heinstein Castle in the 16th century, Alone in the 18th century, and Andromeda Shun in the 20th century. Host possession triggers distinct physical alterations: black hair, pale skin, and green eyes, mirroring his true form. His dormant divine body rests within a marble tomb in Elysion, guarded by the twin gods Hypnos and Thanatos. His original divine form possesses extraordinary, otherworldly beauty, described as angelic despite his realm's gloom. Snow-like skin, long black hair with strands crossing his face, and eyes depicted as yellow in the manga and green in the anime characterize this form. He wears the unique Surplice, silver and gray armor with angelic wing motifs, stored exclusively in Elysion for his true body. This appearance sharply contrasts his nature. His personality centers on absolute pride in godhood, viewing deities as superior to impure, disrespectful humans. He holds humanity in contempt, justifying extermination wars as "cleansing" the world. He feels no remorse for massive loss of life and views his Specter soldiers as expendable tools, deceiving them with false promises of eternal life. Despite this, he harbors complex love for his niece Athena, repeatedly offering her clemency during conflicts, while remaining ruthless toward her Saints, exemplified by cursing Pegasus Seiya with a permanent injury. He manipulates cunningly, exploiting hosts' emotional connections, such as amplifying Alone's hatred by recalling traumatic memories involving Sagittarius Sisyphus. Subtle hints of tragedy or sorrow occasionally surface beneath the cruelty. His immense powers reflect his status as one of the eldest Olympian brothers. He wields absolute control over the Underworld, granting passage between realms, resurrecting the dead, and commanding Specters. Extrasensory perception allows him to detect distant cosmic energies like Phoenix Ikki's presence or Athena's cosmos. His advanced telekinesis surpasses even Hypnos and Thanatos, enabling him to levitate objects, negate attacks, and overpower multiple opponents simultaneously. He absorbs and redirects enemy assaults, repelling attacks while possessing hosts like Alone or Shun. He fully utilizes his Divine Cosmo, or Big Will, unlike his brother Poseidon's restrained power. One ultimate technique, the Greatest Eclipse, requires manipulating the solar system to destroy souls on a vast scale, though it remains unrealized in depicted conflicts. His dependence on a host creates vulnerability; strong-willed individuals like Shun can temporarily resist control, creating openings for enemies. In the Sanctuary arc, his influence indirectly drives the conflict. He resurrects deceased Saints, including former Gold Saints, granting them Surplice armors and twelve hours to kill Athena through a pact pledging allegiance for vengeance. Pandora acts as his primary emissary, overseeing the assault. His strategic acumen exploits divisions among Athena's forces, leveraging resurrected Saints' resentment toward surviving Gold and Bronze Saints. The conflict culminates in Athena sacrificing herself with a golden dagger, revealing a deeper gambit by the resurrected Saints to convey a critical message to her under Hades' unawareness, ultimately enabling the creation of the Athena Cloth, a key weapon against him later.