Regeneration Monster Corps

The Regeneration Monster Corps 再生怪獣軍団 (Saisei Kaijū Gundan) are a squadron of previously-existed and  revived by Grand Flasher who first appeared in episode 9 of the 1972 tokusatsu  series, Assault! Human titled Last Moment of King Flasher.

Last Moment of King Flasher
After Jairock's, Zarizon's, Blanca's, King Takoras's, and Gejiru's initial deployments (and inevitable defeats), as well as King Flasher's overthrowment, Grand Flasher revived the monsters and unleashed them upon Human No. 1. Although just recently battling Giringa, Human No. 1 put up a valiant effort to fend off the monster corps, but was brought to near death. Meanwhile, the hero's brother Junjiro had been following his sibling after noticing his constant disappearances. Walking straight into a climactic battle, Junjiro was stunned to see his brother being killed. Onlooking children used a small device on Junjiro, transforming him into a red-colored Human. With his newfound powers, Junjiro aided Human No. 1 and together defeated the Regeneration Monster Corps.