In the previous episode, Kamen Rider Ark-Zero were effortlessly defeated both Zero-One and Vulcan, despite trying their best to stop him. Looks like Ark is now possessed Jin again and transform as Kamen Rider Ark-Zero in the next episode. With the Ark declares his mission to destroy humanity, what will they do now about the Ark in the next episode?

This is also the debut of Kamen Rider Naki (仮面ライダー亡) and the return of Kamen Rider Ikazuchi (仮面ライダー雷) since his one-shot appearance in episode 14. With this, the MetsubouJinrai.net's Kamen Riders have been fully assembled.

Synopsis

Finally, the Ark has manifested itself as a Kamen Rider and appeared before Aruto and the others! Zero-One and Vulcan were completely powerless standing before such an overwhelming force! This translated into a moment where Aruto is starting to fear the prospects of advancing artificial intelligence innovations beyond human comprehension. Aruto is starting to lose sight of himself, as he doesn't know how to handle the new emergence of the Ark... Meanwhile, a newly revived Ark hands Naki a new Progrisekey...!