Sutekh

Sutekh, also known as Sutekth the Destroyer, was an evil Osirian 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 the destroyer of all living things.

History
Like in the Egyptian myths on Earth, Sutekh was brother to Horus (DW: Pyramids of Mars) and husband to their sister, Nephthys. (MA: The Sands of Time)

The worlds that Sutekh destroyed included his home planet Phaester Osiris as well as Mars. He was known throughout the Galaxy by many names, including Typhonian Beast, Set, Sadok, Seth and Satan. (DW: Pyramids of Mars)

During ancient times, Sutekh's brother Horus and the remaining seven hundred forty Osirians tracked Sutekh down to Egypt and used their powers to imprison him in the Black Pyramid. The Eye of Horus on Mars beamed a signal to suppress Sutekh's powers and hold him prisoner. The tales of the Osirians were remembered in Egyptian mythology. Sutekh still retained a cult of followers, such as Ibrahim Namin. (DW: Pyramids of Mars) Not all of Sutekh's worshippers followed a creed of evil, however. (NA: Set Piece) In the year 1911, the archaeologist Professor Marcus Scarman discovered the inner chamber of the Pyramid of Horus, discovering Sutekh and thereby accidentally allowing him a chance of escape. Sutekh controlled Scarman's corpse, using it and Osirian service robots to construct a rocket aimed at the Eye of Horus on Mars. The Fourth Doctor and Sarah Jane Smith were able to destroy the rocket, however the Doctor fell under the psychic control of Sutekh's will as a result. He was made to take Scarman and the robots to Mars in the TARDIS. Despite the Doctor's attempt to stop them, Scarman destroyed the Eye and freed Sutekh. Hurrying back to Earth, the Doctor defeated Sutekh by trapping him in a time tunnel for thousands of years — longer than the lifespan of an Osirian. (DW: Pyramids of Mars)

Powers and abilities
Sutekh possessed immense power: he could change the course of history and destroy entire stellar systems. He was even able to contain the explosive force of gelignite, although this was difficult and could be easily disrupted by a simple distraction. The Fourth Doctor took Sarah Jane Smith to an alternate 1980, a ruined and abandoned wasteland due to Sutekh's destruction. According to the Doctor, not even the Time Lords could stop Sutekh had he been released from his prison.

He was incredibly powerful and easily able to defeat a Time Lord. His powers became apparent when his eyes glowed green, allowing him to leave a person in agonising pain for centuries. Furthermore, his mental abilities allowed him to easily dominate others, making them puppets to his will. He also appeared to be able to telepathically read other beings like the Doctor and monitor progress several thousand miles away with the aid of Osiran computer techology. This included reanimating corpses for servants, as he did with Marcus Scarman. Sutekh was extremely intelligent and patient.

Sutekh is one of several beings to have assumed the identity of Satan for themselves; others include the Beast, Hades, and the Dæmons.