Questor

Questor was an alien who bumped into the First Doctor, Dodo and Steven in the living jungle of Tropicalus. He and the Doctor engaged in a battle of wits, and Questor was defeated.

Some time later, Questor joined forces with other aliens that had been defeated by the Doctor to try to kill him. He was shot in the face by Bolog, who believed him to be the Doctor in disguise. (COMIC: Death to the Doctor!)

Behind the scenes
In an interview with Jonathan Morris released in The Widow's Curse the description for Questor was given as; "looks like something from The Space Museum ie an extremely cheap 1960s monster. He is wearing overalls with a tin foil 'lightning' design, false eyebrows and a Beatles wig. A frond of seaweed is stuck to his chin. His translation unit looks like an air freshener. It's important he's rendered only in black, white and grey". His monochromatic appearance was referenced within the script when Bolog describes him as looking "lo-fi".