Ultraman Regulos is an Ultraman who first appeared in Ultra Galaxy Fight: The Destined Crossroad. He was originally introduced in Ultra Galaxy Fight: The Absolute Conspiracy as a silhouetted figure who was imprisoned in Narak. Regulos learned the Cosmo Beast Style from Planet D60, an exoplanet orbiting a star in the constellation of Draco.
One day, a comatose Regulos landed on Planet D60 with no memories other than his own name. He was found by Spica, a practitioner of the Cosmo Beast Style of space martial arts. She introduced him to Master Alude, who allowed him to stay on the planet to train in the Cosmo Beast Style while he would recovered his memories, where he would meet and become friends with fellow outsider trainee Dias. He would soon start friendly rivalries with Ultraman Leo and Astra of Planet L77, sparring with them from time to time.