Sutekh

Sutekh (also known as Sutekh the Destroyer or Set) is the main antagonist of Season 16. He is an Osiran who plans to destroy all life in the Universe. He fears all life which might one day challenge his hegemony.

Like in Egyptian Mythology, Sutekh is the brother of Horus and the husband of their sister, Nephthys.

Role
Sutekh makes his first appearance at the end of the third episode of Season 16. The Master confronts the Doctors outside the diner and, using his new portal device, opens a Time Corridor to reveal the Osiran standing before them but unable to move due to the Eye of Horus keeping him in paralysis. However, Sutekh is still able to use his powers to intimidate the Doctors, causing them to open their portal devices and escape into various points in time.

Abilities
Sutekh possesses immense power: he can change the course of history and destroy entire star systems. Even when he's trapped and his powers are limited, he is able to contain an explosive force from miles away. He also has telekinesis, enabling him to levitate items like the TARDIS key. According to the Doctor, not even the Time Lords could stop Sutekh if he was released from his prison.

He is powerful enough to defeat even a Time Lord. His eyes glow green when he is using his powers. Furthermore, his mental abilities allow him to easily dominate others, making them puppets to his will.

Defeat
At the end of Season 16, the Eye of Horus is destroyed by the Ainley Master, freeing Sutekh from his paralysis. Hurrying back to Earth, the Doctors use the remains of a robot named Drathro defeat Sutekh by delaying his trip in a Time Corridor outside the diner by moving the corridor's threshold to the far future, effectively aging him to death.