Shiin Kazamatsuri

Shiin Kazamatsuri (風祭 新), also the second Kamen Rider Shin (仮面ライダーシン), is the son of Shin Kazamatsuri and Ai Asuka in the Japanese tokusatsu movie Shin Kamen Rider: Prologue. His Rider form only appeared in the Kamen Rider Shin SIC Hero Saga.

Prologue
When his parents are being chased by the Foundation as he was a baby, he uses his abilities to help them escape.

SIC Hero Saga
After several decades, Shiin began to investigate the Foundation by himself. The CIA called him "Masked Rider" as his code name. He found a destroyed Cyclone with a battle suit under a bridge after an accident and he decided to put them on and called himself "Kamen Rider Shin".