Theodoi

Theodoi was the first Gegenee, along with others who were created by Gaia.

History
During the First Olympian War, Gaia created a mortal race of six-armed giants called Gegenees to aid the Olympians to fight the Titans. Theodoi and the Gegenees were successful, and they were awarded by Zeus for their honor, bravery, and courage.

Together, Theodoi and the Gegenees moved to a huge island called Gegan and build themselves their civilization. Theodoi became the King of the Island when he led his race into safety. However, their civilization didn't last. When Gaia was commanding her children to destroy the Olympians, Theodoi and his people refused to obey. As punishment, the Gegenees fought against a race of mortal Doliones that invade their island, and destroyed their civilization. Theodoi was the only one who survived and watched all the Gegenee perish. Upset and heartbroken, Theodoi swam through the water and discovered a chain of Islands. He noticed that everything was deserted, and he was the only one who could live alone as a mortal.

Eventually, Zeus came down to him, and offered him a gift of immortality. Theodoi accepted the gift, and was granted a power that he could actually do. He created a mortal race of giants called Rhodian Giants. Together, they build a new civilization. Theodoi became the King of Rhode, and the Rhodian Giants worshipped him, and the Gods of Olympus.

The Son of Neptune
He first appeared in The Son of Neptune where he welcomed Percy Jackson, Gwen Madison, and Bobby to Rhode, and offered them sanctuary. He explained his story about how he created the giants and granting himself immortality.