Prometheus is a member of the Titans of Greek Mythology, one of the forbearers of the Pantheon. He is also a powerful deity in the City of Heroes MMO, responsible for taking away and then restoring the superpowers of heroes in Paragon City.
According to myth, Prometheus helped create mankind to please his fellow gods. But his fellow gods were petty and spoiled. They treated humans like animals and expected undue praise for the "pleasure" of their existence. The worst of these gods was Zeus, the child of Titans and ruler of Olympus.
To teach Zeus a lesson, Prometheus challenged Zeus to choose how humans should give thanks to them. He placed an offering of meat inside the shell of an ox, considered to be offensive to the gods, and placed an offering of bones inside a ball of glistening animal fat, considered favorable to the gods. He then challenged Zeus to choose which "offering" would be acceptable. Zeus chose the fat over the oxen, only seeing the shell instead of what was inside it. Afterward, humans were allowed to sacrifice animal bones stripped clean and layered in fat to the Gods instead of giving up their prized meats.
In retaliation, Zeus took fire away from humanity and ordered no Olympian or Titan to intervene. Prometheus defied Zeus and stole the fire, giving it back to humanity. In retaliation, Zeus chained Prometheus to a huge rock to have his innards consumed by a giant eagle. As he was immortal, Prometheus would never die, and by dawn would be fully healed in time for the eagle to attack again and again and again. It would be Zeus's son, Hercules, who would free Prometheus from his endless torment, but Prometheus would never forgive Zeus for what he did.
Millennia later, Prometheus would be tricked into carrying out his revenge on Zeus.
City of Heroes "Hard Crash"
(See also "Hard Crash")
The mystical mechanizations of Lord Recluse, the incarnate embodiment of the primordial deity Tartarus, convinced Prometheus that Zeus was alive and well in the body of Marcus Cole, aka Statesman. So, much like Zeus stole fire from humanity, Prometheus stole the "fire" of superpowers from all the heroes of Paragon City. This allowed Arachnos to invade Paragon City unopposed.
Statesman was prepared to sacrifice himself to Prometheus, to serve Prometheus's punishment in Zeus's place and be tortured until he could be tortured no more. But Manticore could not stand for it. He shot an arrow into Statesman's chest, killing him. The Titan reluctantly held up his end of the bargain, restoring all the superpowers that were stolen (and giving power to Manticore). Manticore then used Numina to bring Statesman back to life.
While in Ouroboros aiding heroes to fight the threat of Tyrant, Prometheus was made aware of a major shift in the timeline that involved the Menders and a future version of Galatea Powers. Not trusting the Menders to do the right thing, Prometheus turned to the only other expert in time, the former time manipulator Doc Tor.
In order to stabilize the timeline, the two set up conditions to save as many lives in Galaxy City as possible. They created a time echo of Galaxy City, which preserved the civilians in the zone just before the Shivan meteor shower hit until Tor could come up with a way to bring back to the current time.
Prometheus coaxed Galatea Powers to find the time echo, and, with her help, Tor was able to finish the work and save over 2200 people from Galaxy City.
Connection to Ouroboros
According to Doc Tor, Prometheus helped create the Pillar of Ice and Flame, providing the "flame" part of the huge temporal paradox device, and thus made it sentient. It is said that he is in Ouroboros because of a threat so dire that even the Pantheon fear the consequences.
Powers and Abilities
As a Titan of myth, the true scope of Prometheus's power cannot be measured.
In the past he has shown that he can manipulate reality itself so that people can either gain or lose powers. He can also affect minds, as demonstrated by the existence of a time portal in Ouroboros that no Mender knows exists, even though this portal itself is directly underneath Mender Silos. And, as the co-creator of the Pillar of Ice and Flame, he even has power over time.
As a god of knowledge, Prometheus doesn't speak directly to "lesser beings" if he can help it. If he does, he speaks in riddles and vague references. He does this to encourage others to learn on their own. If he communicates to those "lesser beings", it is often through proxy devices.
Very few people can speak directly to Prometheus. That's why he remains in places like Ouroboros. Those who do should consider themselves honored.
(See his Paragon Wiki entry for more information.)
He later appeared in a flashback in "The Guardian Powers" #14.