Osiris
Osiris was the leader of the Osirans. He ruled Phaester Osiris alongside his brother Sutekh. Isis was his sister and wife.
Sutekh, having decided to kill his brother, lured Osiris into a space capsule. Sutekh and his sister/wife Nephthys were able to propel the capsule into space and stop Osiris from mentally projecting himself. He suffocated in the vacuum of space and was unable to project his mind over the great distances. While Isis was searching for him, he was eventually able to project part of his mind into the pilot of her ship, giving birth to his psi-child Horus. (PROSE: The Sands of Time)
After the death of Osiris, Sutekh and Nephthys escaped to Earth, destroying Phaester Osiris along the way. (TV: Pyramids of Mars, PROSE: The Sands of Time)
Osiris returned to Earth years later in the hopes of recapturing it. (COMIC: Spiral Staircase)