Xeriphas

Xeriphas was the homeworld of the psychic Xeraphin race. 140,000,000 years ago, Xeriphas was caught in the cross-fire of the Vardon-Kosnax War and devastated by radiation. The fleeing Xeraphin merged into a gestalt and left for Earth. By the early 1980s Xeriphas had returned to a normal state and the Doctor said that they could return. The Master ended up trapped there. (DW: Time-Flight) Here, he found the android Kamelion, whom he decided to use for his own purposes. (DW: The King's Demons)