Spinoffs

Plot Summary from Wikipedia:
Robotics scientist Keitarō Jin and his son Keisuke become caught up in the campaign of terror by an evil organization known as “GOD” (The Government Of Darkness). They are attacked and the professor’s technology stolen, but before Keitarō dies, he is able to perform surgery on his son. With the last of his robotics technology, he transforms his son into “Kamen Rider X”. Now, to avenge his father’s death and ensure the safety of Tokyo, Japan, and entire world, he battles the monstrous minions of GOD, weidling his powerful “Ridol”, which can be used as a spear, a rapier, or a club, among others. With an exuberant cry of “Set Up!”, he transforms into X-Rider, charging into battle aboard his motorcycle “Cruiser”. In the first 21 episodes, X fights kaijin based on characters from Greek mythology. Soon, the personal soldiers of “King Dark”, the leader of GOD, begin to attack. After defeating them, he faces off against King Dark himself finally ending GOD’s mission of terror, and the world is safe again.
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