An alien from Planet Metron who plans to intrude Earth, also known as "the Hallucination Alien."
It has a long red face rimmed in yellow, a blue body and fin-like hands.
As a beginning point in the invasion of Earth, Alien Metron disguised as a man in a black suit living in Kitagawa-cho. It planned to wipe out humanity by inciting people to fight each other, spreading cigarettes that make those who smoke them more aggressive.

When Dan Moroboshi detects Alien Metron's base, Alien Metron invites Dan to sit down to talk. But it turns out to be a trick as the base is a flying saucer in disguise. Alien Metron catches Dan off guard and flies the saucer out into space aiming to expel Dan.
However, the saucer is soon shot down by Ultra Hawk 1 and Dan escapes and transforms into Ultraseven.
Alien Metron grows in size to fight Ultraseven, but soon realizes that it is no match against him. Alien Metron tries to escape, but is defeated by Ultraseven's Eye Slugger and Emerium Beam.