Pluto is a member of the race of the extra-dimensional Olympians, and thus possesses super strength, endurance, and resistance to injury. He maintains virtual omnipotence in his realm of Hades, capable of nearly any superhuman feat, even creating mystical flame and controlling flame, heat and light, and darkforce. Pluto can create weapons from his fiery aura and even create warps between dimensions. Pluto's main weapon is his signature axe which can focus his powers, and his main accessory is his Helmet of Invisibility.
Pluto is the eldest son of Cronus, ruler of the superhuman extra-dimensional race of Titans, and his wife, the Titaness Rhea.
When Zeus usurped Cronus, Pluto's aided in the war by stealing Cronus's principal weapons from his palace while wearing a helmet of invisibility. Zeus became ruler of the pocket dimension called Olympus and of the race of Olympian gods, and confined the defeated Titan warriors to Tartarus, the darkest section of Hades, the Olympian underworld. He knew that they needed a stern warder and that the brooding Pluto was the only one of his siblings who found life in the underworld suitable to his temperament. Therefore, Zeus assigned ruler-ship of the entire underworld to his elder brother. Pluto was quite pleased with this new role and rarely left the underworld over the following centuries.
The most infamous exception was when Pluto carried off Kore, the goddess of spring, to the underworld, to force her to become his wife. Kore's mother, the fertility goddess Demeter, was outraged, and refused to allow crops to grow in ancient Greece until Kore was returned. Eventually, a compromise was reached, and Kore spends only a portion of the year in Hades with her husband. As queen of Hades, Kore is known as Persephone.
Since the time of his appointment as ruler of Hades, Pluto had populated his realm with the "shades" of mortals who had worshiped the Olympian gods. When the worship of Olympian gods died out, giving way to Christianity, Zeus forbade Pluto from collecting any more "souls." Pluto obeyed the edict resentfully, having become accustomed to an ever-growing number of subjects in his realm. The bitter Pluto finally convinced himself that Zeus had proved himself to be an incompetent leader by allowing the worship of the Olympians to come to an end. Zeus, noting Pluto's increasingly ominous rebelliousness, warned him against attempting to overthrow him and sentenced him to remain monarch of Hades until Pluto could find a willing replacement.
In recent years, during one of Hercules' sojourns on Earth, Pluto appeared on Earth in the guise of Hayden P. Hellman (nicknamed "Mr. Pluto"), a movie producer at California Stardust Studios. Thus disguised, Pluto had the naive Hercules sign a contract that Hercules believed was for appearing in a project film. But in fact, it was an Olympian contract binding Hercules to become Pluto's successor as ruler of Hades. Having signed the contract, Hercules was unable to battle Pluto on his own behalf, but the Asgardian god Thor fought against Pluto's forces to free Hercules. Shocked by the massive destruction wreaked in Hades by Thor, Pluto realized that he loved his kingdom and could not bear to forsake it. Pluto therefore released Hercules from the contract.
But Pluto still wished to add new conquests to his kingdom. He traveled to an alternate future of Earth in which nuclear radiation had transformed many human beings into inhuman-looking mutates. Pluto brought an army of mutates back to his own time to conquer Earth for him. Pluto and his mutates were opposed by Thor, his fellow Asgardians Balder and Sif, and the United States armed forces. Finally, Zeus himself intervened, banishing both Pluto and his mutates to Hades.
Later, Odin, monarch of the Asgardians, physically died. But time had been magically suspended about him so that his spirit would not yet leave his body. Pluto attempted to claim Odin's soul but was opposed by Odin's son Thor and by the Asgardian death goddess Hela. Rather than allow Pluto to deprive her of Odin's soul, Hela restored Odin to life. Odin interrupted the battle between Thor and Pluto, and Pluto returned to Hades. Still later, Pluto and his nephew Ares conspired to provoke a battle between Thor and Hercules. But Thor and Hercules learned of the deception, and Thor managed to defeat Pluto on Earth.
Sometime later, Pluto made alliances with other death gods of other dimensions, and then demanded that Zeus command Hercules and the goddess Venus to marry Pluto's allies Ares and Hippolyta. Zeus, fearing that Pluto would otherwise lead the other death gods in an attack on Olympus, at first agreed. In fact, Pluto still intended to conquer Olympus; Pluto believed that Hercules and Venus were the only two Olympians who could prevent his taking over Olympus, but, according to Zeus's law, once they were married to Ares and Hippolyta, Hercules and Venus would be unable to oppose them in combat. But finally, Zeus called Pluto's bluff, withdrew commands for the marriages, and sent Pluto back to Hades. Pluto has met with the death-gods of other pantheons on yet another occasion, when the primordial Demogorge threatened all gods.
Pluto has recently been usurped by the Chaos King Mikaboshi despite his best efforts to resist, and was placed under his thrall alongside Hela and the other death gods until Hercules manages to indirectly banish him to the Continuum bubble universe.