S1·E21 Who is Sosai X?

A horse owned by a doctor who is an authority in the area of cyborgs, participates and wins with an astonishing performance at the world-famous horse grand prix. When Nambu sees this video, he guesses that this horse is a cyborg. He orders the Science Ninja Team to guard the Doctor so that his astonishing cyborg technique is not abused.

But when Ken and the others arrive, it's already too late. Only one Galactor badge has been left behind and the Doctor has vanished.

Dr. Henjinman has been brought to the base where he recognizes X's real face. He threatens X, saying that he will reveal his secret if he is not made X's representative. X reluctantly agrees.

The Doctor's cyborg horses attack a meadow. The Science Ninja Team pursue them and sneak into the base. Inside, they find the doctor standing before X to reveal his face, just as he wanted. The doctor falls down as he's hit by a light rays projected by X when Katse pressed a button. Katse orders the horses to attack the city and flees. The Science Ninja Team escapes and blows up the base.

Dying, the doctor tells them to press the buttons on the horses' backs. After the Science Ninja Teams has pressed the buttons on eac of the horses, he activates the self destruct mechanism of the horses and silently dies.