KORBY or Katsuya Kobayashi is a Japanese voice actor, disc jockey and narrator. He provided the voice of the Build Driver and Nebulasteam Gun in Kamen Rider Build. He also provided the voice of the Kamen Rider Build Gashat. He was also the chorus of the New Kamen Rider song Kagayake! Hachinin Rider, which was the theme of Eight Riders vs. Galaxy King and the second ending of the show.

Filmography