Third Drax
Drax's third incarnation was, much like his predecessor, a renegade Time Lord with a knack for tinkering and engineering.
Biography
Shortly after regenerating, Drax gained the map to Altrazar. In order to stage a con that involved the use of all nine of his future incarnations, Drax required a Blinovitch Limitation Effect limiter to avoid temporal catastrophe. Needing a fall guy, Drax conned the Fourth Doctor into stealing the Blinovicth Limitation Effect limiter, which was what allowed his future incarnations to successfully cooperate on this scheme and others in the first place. By the time the Doctor and Romana realised that Drax must have known he would have been arrested over different incarnations, they realised the truth about McCormick and her men, and by the time they returned all of Drax's incarnations had escaped in their TARDIS. (AUDIO: The Trouble with Drax)