This article is about a/an episode in Kamen Rider Decade.

Rider War (ライダー大戦 Raidā Taisen) is the first episode of Kamen Rider Decade. It foreshadows the series' climax event and introduces several main characters and the setting. It also leads into the series' first two-part arc.


A young man named Tsukasa Kadoya learns of a war that involves all past Riders, and, as Kamen Rider Decade, he must protect their worlds, even if it means the destruction of his!


After Natsumi Hikari has a nightmare of every Kamen Rider including Kuuga in his fearsome Ultimate Form, being defeated by a figure called Decade, she helps her grandfather Eijiro deal with unsatisfied customers. The photographer, Tsukasa Kadoya, seems to be at fault, but he simply tells Natsumi the photos are bad because he does not belong in this world. After the argument, various holes in reality open, allowing the Orphnoch, Undead, Makamou, Worms, Imagin and Fangires to start terrorizing their world. In the bedlam, she finds a corroded belt and book, recalling it as Decade's from her dream. She gives Tsukasa the belt and book, allowing him to transform into Kamen Rider Decade by using a card from the book and inserting it into the belt. Using other cards, he fights the various monsters that have invaded his reality by transforming into Kamen Riders Kabuto, Faiz, and Hibiki. Back in his own reality, Tsukasa is warned by Wataru Kurenai that his reality is being superseded by the nine previous Kamen Riders' realities. He must go to their worlds and defeat the other Kamen Riders to save his own world, while Wataru keeps it frozen in place. Back in the Hikari Studio, Eijiro reveals a large photo that shows another world. Stepping outside, Tsukasa finds himself in this world as a police officer while Kamen Rider Kuuga appears to aid the police against two Gurongi.

Rider Cards

  • Card Used:
    • Kamen Ride - Decade, Kabuto, Faiz, Hibiki
    • Attack Ride - Clock Up, Auto Vajin, Ongekibou - Rekka
  • Forms:
    • Decade, Decade Kabuto Rider Form, Decade Faiz, Decade Hibiki


Guest stars

Suit actors

Appearing monsters


DcD EP1 Error.png

  • Before Decade inserts Kamen Ride card of Hibiki to Decadriver, the Hibiki's symbol is already seen in there.
  • Ongekibou - Rekka is immediately activated right after Decade transforms into Hibiki without the actual Attack Ride card being used.
  • Onodera's Arcle Belt is activated before he could press the switch.


Nine Worlds #1: Kuuga

DVD releases

Kamen Rider Decade Volume 1, DVD cover

Kamen Rider Decade Volume 1 features episodes 1-5: Rider War, The World of Kuuga, Transcendence, Second Movement ♬ Prince Kiva and The Biting King's Qualifications. [1]

Kamen Rider Decade Box, Blu-ray cover

Blu-ray Box comes with all 31 episodes.


External links

Community content is available under CC-BY-SA unless otherwise noted.