Phaester Osiris, also called the Throneworld (AUDIO: The Ship of a Billion Years) and stylised as Phæster Osiris, (PROSE: The Sands of Time) was the home planet of the Osirans. It was a hot and dusty planet, (PROSE: Legacy) located in the constellation of Orion (PROSE: The Sands of Time) and having one moon, Beta Osiris, (PROSE: Scarab of Death) as well as the energy production facility Amenthes, orbiting it. (COMIC: Old Girl) Signs of the Osirans' civilisation could be found on the planet, such as the especially tall pyramids. (PROSE: The Dark Path)
Circa 5000 BC, Phaester Osiris was ruled by Horus and Sutekh. When Sutekh started his reign of destruction, Phaester Osiris was one of the targets. Only Horus and seven hundred forty other Osirans survived the destruction of their homeworld. (TV: Pyramids of Mars)
In 3985, the Braxiatel Collection funded an expedition to investigate the planet. Professor Rhukk helped discover the Horun ruins. (PROSE: Legacy)
Though Phaester Osiris was eventually destroyed by Sutekh, it existed as recently as the 40th century. (PROSE: Scarab of Death, PROSE: Legacy)