Name: The Master

Real Name: Koschei

Aliases: Harold Saxon, Professor Yana, Missy, Bruce

Occupation: Renegade Time Lord, archenemy of the Doctor

Identity: Publicly known as Harold Saxon, a human politician

Citizenship: Gallifreyan

Place of Birth: Gallifrey

Known Relatives: None

Group Affiliation: None

Education: Trained in Time Lord Academy on Gallifrey

First Appearance: "Terror of the Autons" (Doctor Who Season 8, 1971)

History: The Master is a Time Lord, like his nemesis the Doctor, but he turned against his people and became a renegade, using his knowledge of time travel and advanced technology for his own nefarious purposes. He has a long history of trying to conquer the universe, destroy the Doctor, and cause chaos and destruction wherever he goes.

The Master has taken on many different forms over the years, using his shape-shifting abilities to blend in with different societies and manipulate events to his advantage. He has been a human politician named Harold Saxon, a kindly old professor named Yana, and even a female incarnation known as Missy.

Powers and Abilities: The Master is a genius-level intellect and a master of manipulation and deception. He has access to advanced technology that allows him to travel through time and space, as well as create powerful weapons and machines. He is a skilled fighter, both with his bare hands and with a variety of weapons, and has incredible stamina and endurance. He also possesses the ability to regenerate his body when it is damaged or destroyed, although he only has a limited number of regenerations.

Weaknesses: The Master's desire for power and control often leads to his downfall, as he becomes overconfident and underestimates his enemies. He has a tendency to make rash decisions and act impulsively, which can lead to him making mistakes that cost him dearly. His arrogance and belief in his own superiority also makes him vulnerable to manipulation and mind games.

Threat Level: The Master is considered one of the most dangerous individuals in the universe, due to his vast knowledge and power, as well as his willingness to use them for his own ends. He poses a significant threat to anyone who crosses his path, and has been known to cause massive destruction and loss of life in pursuit of his goals. His ongoing feud with the Doctor is a constant source of danger for all those caught in the crossfire.