The offspring of Gaea the Earth and Uranus the heavens became known as the Titans of Myth. Two such beings were Hyperion and Thia, known as Titans of the sun. Although these Titans of Myth enjoyed god-like status, Gaea also had a number of less attractive offspring, whom Uranus banished to the pits of Tartarus.
Gaea persuaded Cronus to kill Uranus and release her brood. Instead, he killed Uranus and then invited Hyperion and all the other Titans of Myth to join him in the paradise of a subjugated Earth.
Many years later, Cronus' own son Zeus released his siblings and the brood from Tartarus and led a successful revolt against the Titans of Myth. Zeus banished them all to imprisonment in the stone pillars of Tartarus. Thousands of years later, it was Thia and then Hyperion who escaped. They enrolled the help of an unsuspecting Wonder Girl (Donna Troy) and released the other Titans of Myth.
The Titans of Myth then attacked Mount Olympus, seeking reenge against Zeus and the others. After two epic battles, Hyperion's wife Thia went insane, slaying her fellow Titans, Crius, lapetus and Tethys. Her killing spree only stopped when Hyperion sacrificed his own life to destroy her.
With Hyperion and the others dead, a contrite Zeus invited the surviving Titans to go and live with him in peace inside Mount Olympus, and they accepted.
Somehow Hyperion must have survived. He and the other New Titans, along with Donna Troy who had died and been reborn, took up residence on New Chronus. They were waging war against Minosyss a planet where a great weapon was hidden. It was a complete slaughter, the warriors of the New Titans massacring the natives.
One of Donna Troy's adoptive siblings called out for the Teen Titans, sending a god gate to bring them to Minosyss. The Teen Titans sided with the Minosyns, trying to make Donna remember them. Donna did, though she feigned ignorance for a longer…
The weapon Minosyss hid was a sun eater, capable of rending the space between dimensions. Donna opened a gate, pretending it would lead the New Titans to a universe they could shape to their wills. Instead she trapped several of them in Tartarus, a hell dimension. Hyperion had not gone through the gate, and fought back. The sun-eater was released, and consumed the sun god.