Trantis
Trantis was a representative of his home galaxy when he allied himself with the Daleks in their plan to conquer the Solar System. When the Daleks got back their taranium core from the Doctor, they tested their Time Destructor on Trantis. When the device did not kill him, they discovered that the Doctor had given them a fake core. They then exterminated Trantis. (DW: Mission to the Unknown / The Daleks' Master Plan)
Behind the Scenes
While publicity photos, mainly from Mission to the Unknown, and some telesnaps have shown Trantis with tendrils hanging from his face, Day of Armageddon (the only surviving episode of The Daleks' Master Plan to feature Trantis) shows Trantis looking much like a normal human, except for his jagged, sharpened teeth.