Rhinoceros Mutant

The Rhinoceros Mutant appeared in 1987 TV series called Kamen Rider Black. The Rhinoceros Mutant (サイ怪人 Sai Kaijin) is a rhinoceros Gorgom monster. In a plan to have humans fight each other, Gorgom used a grasshopper serum in a champaign. To help those people who already had the serum and to prevent Kamen Rider Black from interfering, the Rhinoceros Mutant was unleashed to help them and it first brutally killed four gang members. In the first battle, it damaged Battle Hopper (whom was revealed to have quick-healing powers). In its second battle at Honmoku Docks, he broke off the Rhinoceros Mutant's front horn and Battle Hopper rammed the Rhinoceros Mutant. The Rhinoceros Mutant was wounded by both before being destroyed by the Rider Kick.

Rhinoceros Mutant later appears as one of the Phantom Mutants that assist Dogfish Mutant.

Rhinoceros Mutant later appears as one of the Phantom Mutants summoned by Fly Mutant through Yuki. It disappeared after Makoto uses his psychic powers to expel Fly Mutant from Yuki.

Rhinoceros Mutant was revived along with four other monsters, Goushima, Agito, Garai, and Zu, by Shadow Moon. These five revived monsters were defeated by Kamen Riders ZO and J.

In the World of Black, the Rhinoceros Mutant becomes a member of Dai-Shocker when Golgom joins the alliance. Summoned to the World of Black RX by Apollo Geist to convince Schwarian of the Crisis Empire to join Dai-Shocker, he is summoned again to help protect Apollo Geist from Black RX, only to be quickly destroyed by Black's Rider Punch.

Powers and Abilities
It can charge, ram into things, has super-strength, and it attacks with its horns.