Umbra is a massive, bio-mechanical computer the size of a planet's core, who rules as leader of the evil SHADOW organization. He (if the machine can be called a "he" - though it does utilize a masculine personality and voice) appears to be a vast globe, possessing a mouth, five eyes, and a vestigial nose. Despite his massive size (or perhaps in direct correlation to it), Umbra has no means of directly battling his foes, and therefore instead chooses to employ giant monsters and sinister aliens in combination with his own elaborate plans. These he uses to combat the Galactic Patrol, which he considers a threat to his galactic rule.