Pengallia

Pengallia was an infamous Time Lord tyrant from before the Infinity Doctor's generation. She was spoken of similarly to Marnal and Morbius. Some believed that the Doctor's revolutionary nature would lead him down a similar path to Pengallia. (PROSE: The Infinity Doctors)

Behind the scenes

 * Pengallia and her story are outlined in the second issue of Adrian Middleton's fanzine Apocrypha. She originates from Middleton's unpublished fanfiction The Great Crusade.
 * Middleton later published a story on fanfiction.net which showed the Fourth Doctor and Romana I dealing with Pengallia's legacy, titled Blink of an Eye.