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
Bolog describes Questor as looking "lo-fi" due to his monochromatic appearance. Jonathan Morris' script, with extracts printed in The Widow's Curse comic collection, specifies Questor's appearance as an "extremely cheap 1960's [sic] monster", which was to be "rendered ONLY IN BLACK, WHITE and GREY".