Rhea is Kronos’s wife, and the Queen of the Titans. Pontos released Rhea at the same time as the other Titanesses, Okeanos and Kreios. Like the rest of the Titans, she fought against the Olympian gods, her children, in the ancient Titanomachy and was sealed within her Soma as punishment.
Rhea is the daughter of Uranus and Gaia (the Sky and Mother Earth respectively), and one of the twelve Titans. She married her brother Kronos after he conquered Uranus, and became the mother of the six original Olympian Gods (Hades, Hestia, Demeter, Poseidon, Hera and Zeus). Upon overthrowing their father Uranus, Kronos received a prophecy fortelling his own downfall at the hands of one of his children with Rhea. Each time Rhea gave birth to a child, Kronos swallowed the infant to prevent the prophecy from happening. Appalled, Rhea secretly gives birth to her sixth child, Zeus, and had him hidden away with the help of Gaia. She then deceived her husband by giving him a large stone wrapped in a blanket to swallow instead of her baby. She supported the Titans in the fight against the Olympian gods, but was later betrayed by her sister Mnemosyne. After the defeat of the Titans, Zeus sent Rhea to Tartarus along with her husband and other siblings.
Saint Seiya: Episode G
She was awakened by Pontos along with nine other Titans, including her sisters. Her husband also awakens when Leo Aiolia was going to attack, but Rhea countered the assault with Themis summoning the Ge Pythons against Leo and Capricorn Shura but upon the arrival of Taurus Aldebaran, she is forced to transform the stone serpents in a giant hydra-like form. Aldebaran kills the creature and saves his comrades.
Rhea is later shown summoning the Fire Lizard to destroy the Ice Coffin blocking the entrance to the Labyrinth where Kronos is imprisoned. She participates in a fight between her husband and Aquarius Camus. However, the fight is unfinished when she is turned to stone by a large cosmos.