Hades

Hades was an Immortal, known in Greek mythology as the ruler of the underworld. (PROSE: Katarina in the Underworld) He dwelt in the Land of Fiction. (AUDIO: The Wrath of Medusa) In later centuries his pseudonyms while living among humanity included Niccolo Machiavelli, Cardinal Richelieu, and Maximilien Robespierre, and in the 20th century Hadley and Colonel Nicolevic. (PROSE: Deadly Reunion)

King of the Underworld
Hades was approached by the First Doctor on Katarina's behalf. Hades refused to overrule his judges' verdict that Katarina was neither good nor evil. However, his wife, Persephone, convinced him that Katarina deserved to enter the Elysian Fields. (PROSE: Katarina in the Underworld)

Niccolo Machiavelli
During the 16th century, Hades, thinking that his time to rule Earth had come, established himself in Italy as a politician, calling himself Niccolo Machiavelli. (PROSE: Deadly Reunion) Machiavelli once met the First Doctor, Steven Taylor and Vicki Pallister when their TARDIS landed in his house in Florence in 1514. (AUDIO: The Ravelli Conspiracy) Hades's attempt to take over the world as Machiavelli was ultimately unsuccessful. (PROSE: Deadly Reunion)

Cardinal Richelieu
In the 17th century, Hades lived in France as a clergyman and politician, now calling himself Cardinal Richelieu. (PROSE: Deadly Reunion) Richelieu encountered the Fifth Doctor in 1626 (AUDIO: The Church and the Crown), and later met the Twelfth Doctor in 1695. (COMIC: Terror of the Cabinet Noir) Hades's attempt to take over the world as Richelieu was also unsuccessful. (PROSE: Deadly Reunion)

Maximilien Robespierre
In the 18th century, Hades lived as the French revolutionary Maximilien Robespierre, and was a central figure in the Reign of Terror. (PROSE: Deadly Reunion) The First Doctor and his companions encountered Robespierre in 1794; he was subsequently executed. (TV: The Reign of Terror)

Colonel Nicolovic
In the 20th century, Hades, calling himself Nicolovic, attempted to orchestrate World War III. He was stopped by his brother Poseidon and forced to return to the Underworld. (PROSE: Deadly Reunion)

Appearance
When the First Doctor and Katarina met Hades in the Underworld, he appeared as a slight, bearded man with flowing auburn hair. He was naked apart from a length of white cloth tied around his waist, and carried a battered helmet that could make him invisible. When angered, he grew much taller, and was surrounded by a fiery aura. (PROSE: Katarina in the Underworld)

Since Machiavelli, Richelieu and Robespierre were all identities of Hades, they all had the same face, a fact which could be discerned by carefully comparing portraits of them. (PROSE: Deadly Reunion)