Sutekh

Sutekh, is an evil Osirians who planned to destroy all life in the universe. He feared all forms of life which might one day challenge his hegemony and so became Sutekh the Destroyer, the destroyer of all living things. This included his home planet Phaester Osiris and Mars. He was known throughout the Galaxy by many names, including the Typhonian Beast, Set, Sadok and Satan.


 * Sutekh's usage of Satan is a tricky matter. Many other beings have used the same name or personality, including the Beast, Hades and the Dæmons. It's possible they knew about each other and were in league with each other. Another possibility is that they used the name at different times and didn't come in contact with the others.

Sutekh's brother Horus and the remaining 740 Osirians tracked Sutekh down to Ancient Egypt and used their powers to imprison him in a pyramid on Earth. The Eye of Horus, located on Mars, beamed a signal to suppress Sutekh's powers and hold him prisoner. The tales of the Osirians were remembered in Egyptian mythology and Sutekh was able to gain followers, like Ibrahim Namin.

In the year 1911, the archaeologist Professor Marcus Scarman discovered the inner chamber of the Pyramid of Horus, discovering Sutekh and allowing him a chance of escape. Scarman's corpse was used to construct Osirian service robots and a rocket aimed at the Eye of Horus on Mars. Though the Doctor attempts to destroy the rocket eventually suceeded, he was taken over by Sutekh's will and made to take Scarman and the Robots to Mars with the TARDIS. Though the Doctor attempted to stop them, Scarman succeeded in destroying the Eye and freeing Sutekh. Hurrying back to Earth, the Doctor was able to defeat the freed Sutekh by trapping him in a Time Tunnel for thousands of years — longer then the lifespan of an Osirian. (DW: Pyramids of Mars)


 * Sutekh seems to have immense power, since he was shown to be able to change the course of history. The Doctor took Sarah Jane Smith to an alternate 1980, which was a ruined and abandoned wasteland. Other evidence would suggest that it is very dangerous and difficult to change the future.