An alien race that planned to assassinate Ultraseven for standing in the way of their plans to dominate the Earth. Alien Guts can use illusion and teleportation abilities to confuse their enemies, using attacks such as firing beams from their eyes and hands.

After they sent the Bold Strength Monster Aron to attack Ultraseven while they analyzed his abilities, several Alien Guts left their alien ship and descended to Earth. They made false reports to the Ultra Guard several times to lure out Dan Moroboshi aka Ultraseven from the base, and then they destroyed Dan’s capsule monster Windom by shooting it with destructive beams from their saucer, but they let Dan escape.

Later, after they’d forced Dan to transform into Ultraseven, Alien Guts used its illusion and teleportation abilities to make Ultraseven use up all of his energy and capture him, and then they announced his execution to the world.

They then tried to assassinate a woman called Ayako Natsu for possessing a diamond that produces the Magnerium Energy needed to revive Ultraseven but failed. The Ultra Guard used it to successfully revive Ultraseven, and he retaliated with a combination of Eye Slugger attacks and Handshake Beams to blow up the Alien Guts along with their flying saucers.