Kamen Rider SD (ou Kamen Rider Super Deformed) é o título coletivo para uma série de mídias lançadas nos anos 1990, que são baseadas nos populares Kamen Rider da Toei . Possui versões super-deformados des vários Kamen Riders, com destaque principal para Kamen Rider Black RX. Foram colocados em um mundo de desenho animado , onde cada inimigo dos Riders tem se unido sob o comando do "Great Leader" da "Gran Shocker".
Neotopia is a world where humans and robots live in peace and harmony. However, it is suddenly invaded by the evil forces of the Dark Axis. The Dark Axis is trying to change all organic life forms into stone, and take control of the AIs of all the robots and mobile citizens. To fight against this invasion, the Super Dimensional Guard (S.D.G.) is secretly formed. Captain Gundam, the hero of the S.D.G., is joined by Shute, a brave young boy whose encouragement and support helps him accomplish his missions.
