Pollux (Thinking Warrior)

 was the beta version of the intelligence core for Perseus Dynamics' Peacekeeper project. He and the alpha version, Castor, were sentient.

Castor grew distressed over the many changes made to his programming, which caused him memory problems. He eventually asked Pollux to destroy the most recent versions of him. Pollux faked an attack on Perseus, in which large amounts of data were wiped. When the Eighth Doctor investigated the incident, he deduced that Pollux was responsible. (PROSE: Thinking Warrior)