Corsair

The Corsair was a Time Lord known to The Doctor as "one of the good ones". His signature emblem was a classical depiction of the mtyhological Oroborus: a snake devouring its tail. According to The Doctor, he had a copy of the emblem tattooed onto his body after each regeneration — even when he regenerated as a female. Without it The Corsair didn't feel like himself. In his last known regneration it appeared on the inside of his right forearm.

The Corsair was presumably killed by the entity known only asThe House: a disembodied being that fed on artron energy it harvested from captured TARDISes. The Corsair's left arm had been stitched onto the being known as "Auntie", a composite humanoid creature that served as The House's slave. Her counterpart, "Uncle", recieved "the spine and the kidneys". Presumably the loss of these parts was lethal and The Corsair went the way of House (The Doctors Wife)'s numerous other Time Lord victims. (DW: The Doctor's Wife)