Osiran

The Osirians (also known as Osirans) were a race of powerful and intelligent humanoids.

Physical Characteristics
Osirians, despite their name, look somewhat like traditional depictions of Set. They have grey skin, donkey-like heads with large, square ears and bright green eyes(DW: Pyramids of Mars). However, those of high status in the Osirian Court are able to change their appearance, adopting a series of different animal heads according to whichever is in fashion (MB: The Ship of A Billion Years). They have expanded brain-cases and a cerebrum like "a spiral staircase", which means they particularity like puzzles. Osirians have advanced psychic powers, including mental projection and telepathy. They can also live for thousands of years, even without sufficient food or water. (DW: Pyramids of Mars)

Osirian curry was best served close to absolute zero (ST: UNIT Christmas Parties: First Christmas) which suggests an especially resilient digestive system.

At least one member of the Osirian Court was of an entirely different species to the others; Thoth who has dominion over time (MB: The Ship of A Billion Years).

Technology
Osirians have very advanced, but stylized technology. One common example of Osirian products are the Osirian service robots. They are thin robots with a wire-framework to give them a more humanoid shape and are powered by a cytronic particle accelerator. They had immense strength and could be controlled by a special ring. These robots were wrapped up in specially treated wrappings which gave them the appearances of mummies. Sutekh used several simple Service Robots to do his bidding, while more ornate robots were used on the pyramid of Mars.

Other Osirian technology includes a force field created by generator loops in canopic jars, Time Tunnels embedded in a sarcophagus, a rocket in the shape of a pyramid and technology activated by certain signs. Despite the unusual design, the Osirians are thought to have technology as powerful, if not more powerful, then the Time Lords. (DW: Pyramids of Mars)

History
The Osirian Court exists, like Gallifrey, in a special relationship to the timeline of the wider universe; Its past sometimes overlapping with Gallifrey's future (MB: Coming to Dust) and Earth's ancient myths sometimes recording events which have yet to transpire for the Court (MB: The Ship of a Billion Years). Regardless of the details, the Osirians are evidently an ancient species, having been a major power since at least 150 million BCE. They were involved in the Millennium War in which they were able to stop the creation of a wormhole in the Horsehead Nebula which would have caused massive damage. They were also involved in the final attack against the Mad Mind of Bophemeral. (DW: The Quantum Archangel)

Although spread across the cosmos, Osirian culture was principally focused on two sites; the Throneworld and the Ship of a Billion Years, the immense vessel which carried Ra, Nut and their attendant pantheon through the heavens.

The Throneworld, Phaester Osiris, was governed by Osiris himself and and his brother Sutekh. Until Sutekh serupticiously slew Osiris and buried his corpse underneath a cache of Faction Paradox reproductive technology. In a parallel to the Egyptian myth of Osiris's dismemberment, the ruined technology interacted with Osiris's biomass and caused it to be remade in fractured and partial forms. Again as in the myth, one of the products of this scattering (most likely the baby Lucita Marne) would result in the birth of Horus (MB: The Ship of a Billion Years).

The Osirian timeline does not run parallel to humanity's, so despite the above events occuring in what we would understand as the Eighteenth Century, from the perspective of the Court they precede the situation 7,000 years ago, by which time Horus had grown to rule Phaester Osiris alongside Sutekh.

While Horus was a relatively just ruler, Sutekh was a ruthless conqueror who set out to extinguish all life in the universe. He was feared throughout the galaxy and was on the way to even defeat the Time Lords. He also caused the destruction of Phaester Osiris, which wiped out most of the Osirians. The 740 remaining Osirians, presumably those who had been aboard the Ship of a Billion Years, were led by Horus in battle against Sutekh, finally defeating him on Earth. Instead of killing him, they trapped Sutekh in a Egypt, having a pyramid on Mars relay a beam to paralyse him. The defeat of Sutekh led to the creation of Egyptian myths about their gods and their technology influenced the styles of the Egyptians.

By 1911, Sutekh was finally discovered by Marcus Scarman and Sutekh was able to control him. He used Marcus Scarman and several Service Robots to construct a missile, with which he would destroy the pyramid on Mars, freeing him to destroy all life in the universe. (DW: Pyramids of Mars)