Zarka was the chief of the Skirkons who came to Vortis and enslaved Menoptera to mine for Galvinium X, hoping to use the explosive power of the mineral to conquer the universe. He captured the First Doctor and planned to kill him unless the Menoptera surrendered, but the Doctor was rescued by John and Gillian. Zarka died when his base was destroyed. (COMIC: On the Web Planet)
