The crossover between Kamen Rider W and Kamen Rider Decade.
Tropes
- Cerebus Retcon: Natsumi going from tsundere comic relief to Tsukasa's killer in The Last Story.
- Chekhov's Gun: The photograph of Tsukasa that was taken by Natsumi near the beginning of The Last Story, which is what is used to revive Tsukasa for the final battle.
- Defeat Equals Explosion: Exaggerated, with not just monsters, but defeated Kamen Riders.
- Early-Bird Cameo: The Stinger features Ryu Terui, Kamen Rider Accel.
- Fake Shemp: Among the Nine Worlds' Riders, the actor for Takumi Ogami (A.R. Faiz) could not be secured, so he is voiced by Kenji Akabane.
- The Remnant: Super Shocker in The Last Story, formed from the leftovers of Dai-Shocker's army.
- The Stinger: Ryu Terui arrives in Futo, observing that Double is not the only Rider in the city now as he produces his Accel Memory.
