Jewel Beetle Mutant (21) - A jewel beetle monster. It can fly, shoot beams out of its eyes, and emit insects out of its mouth which can take over a person's nervous system. Jewel Beetle Mutant was used by Gorgom to take over Battle Hopper. Jewel Beetle Mutant lured out Kotaro by holding a child over the side of a building so that Battle Hopper would attack Kamen Rider BLACK. This monster sent more of its insects which Kotaro spotted later that night and tried to fight them off which failed when two of the insects infected Battle Hopper. While Kotaro pursued it on the Road Sector, Bilgenia hopped onto the Battle Hopper until it threw him off and Bishium explained that Battle Hopper takes orders from no one now and Battle Hopper rampaged the streets. Kotaro headed over to Iwagami Pass where he battled Jewel Beetle Mutant in order to get Battle Hopper back and prevent a missile from blowing up Mammoth Dam. He cut off Jewel Beetle's wings. Kamen Rider BLACK killed him with the Rider Kick, disarmed the missile, and battled Battle Hopper with the Road Sector to get the insects out of it.