Ritskaw

Riskaw was a Sontaran Commander. He was an "old friend" of Psychic Surveyor Kragar.

Biography
After finishing his investigation of the Flux, Kragar called Riskaw on his ship. Riskaw was excited by the news of a greater cataclysm than had ever been known, deciding to use the opportunity to strike other species while they were at their weakest; he soon ordered an attack just as Earth was bearing the brunt of the Flux cloud. (TV: The Halloween Apocalypse)