The eighty-fourth episode of Kamen Rider.
This episode is notable for being the first episode in the franchise to be directed by Shotaro Ishinomori, and the only episode in the original series to be co-written by him.
- Combat Tentacles: Isoginjaguar has these surrounding his mouth and right arm, which he can use to restrain Rider #1.
- Creator Cameo: Shotaro Ishinomori appears as a hapless fisherman who got attacked by Isoginjaguar.
- Defeat Equals Explosion: Averted. Isoginjaguar simply reverts to Yosuke after Rider 1 destroys the device in his brain that forcibly transforms him.
- Finishing Move: Isoginjaguar is defeated by Rider 1's Rider Point Kick, which reverts him to normal.
- Involuntary Shapeshifting: Unlike most of the Shocker and Gel-Shocker Kaijin, Yosuke still retains his consciousness and is forcibly morphed into his monstrous form by General Black.
- Monster of the Week: Isoginjaguar, a sea-anemone/jaguar hybrid.
