Thrakken
From Tardis Wiki, the free Doctor Who reference
Thrakken was a Dalek commander posing as a humanoid soldier who served on the Neverwhen planet front of the Last Great Time War. He tricked the War Doctor into helping them attack the Gallifreyan forces. When he evolved to become a Dalek again he tried to exterminate the War Doctor. (AUDIO: The Neverwhen)