Argaabil
From Tardis Wiki, the free Doctor Who reference
Argaabil was a worker at the Furnace, and a member of the Brotherhood of Rexulon. He told Kaquaan and Jamie McCrimmon that the Brotherhood had taken Cosmae. When Argaabil escaped and told Zaitabor what he had done, Zaitabor killed him for his betrayal. (PROSE: The Menagerie)