Kamen Rider Decade is a world-centric character in Kingdom Hearts: Dual Paths and a Guest in the Modern Province. Like Kamai and Phayne, he is an off-worlder summoned to this dimension by an unknown force in order to fix anomalies unique to his origins, all the while trying to discover who he is.
In actual publications, Decade was a Kamen Rider created to celebrate the anniversery of previous entries into the series. The show involved Decade being warped to alternate versions of these past figures' dimensions in order to undo anomalies threatening to destroy the entire multiverse. When in these dimensions, Decade is always dressed in different garbs or given certain items that serve as hints to his current objective.
Journal Entry: "A masked fighter tasked with fixing the anomalies within other dimensions, all the while seeking to discover his true Identity. His reason for being in the Province is unknown, but if he's fighting the Remnants, can he really be a 'Destroyer Of Worlds?'"
Tsukasa Kadoya, also Kamen Rider Decade, is a photographer who had found his way into the house of a family of photographers by unknown means. He is told by a nameless figure that he is the key to solving anomalies in nine dimensions that, if left unchecked, will destroy reality. The incentive? The discovery of his true identity. Whil this happens, the photographer's daughter receives a strange vision of a Kamen Rider Civil War, as well as a grueling image of Decade at the epicenter.....
In Phayne's story, Decade is warped to the World of the Shinkengers, in the garb of the clan's silent servants. This disguise is quickly discarded when Diend, Decade's rival, reveals that a monster has stolen his transformation device. The two Riders eventually find the culprit: The Remnant Identitus. Phayne and Genta Umenori (Diend's pursuer) join them against the enemy, but they aren't enough. After luring the monster into a less populated area, the Shinkengers intervene. All of them focus their attacks against the enemy and eventually put it out of comission. All stolen items are returned to their respective parties. Soon after, a cloaked figure launches an attack on Phanye, who along with Decade and Genta, chases him thoughout the Province. Unfortunately, he escapes after a brief skirmish. With nothing left to do, Phayne shares a handshake with Decade and Genta before leaving the world. No sooner does Phayne leave that a garbed man approach the two Riders. Events after that are unknown.
The game's epilogue shows Decade participating in a massive battle against many other transformed figures, (Diend among them) presumably emulating the actual show's Rider War, in which he is integral.
As a Guest
Decade joins Phayne and Genta in their battles against the Identitis. Decade is not considered an actual Party Member, and as such, cannot be customized, has invisible stats, cannot be defeated, and does not appear in the Pause Menu. During the fights, Decade will attack any clones Identitus sends out with a series of physical attacks; and will heal Phayne once if his HP is below the half-way point.
As a D-Link
After completing the Modern Province, Phayne will forge a D-Link with Decade. This D-Link's Ability Deck consists of physical attacks, all themed after the sword. When the D-Link is established, Phayne is given an alternate form of Decade's armor for the duration of the Link. This is only a cosmetic change and has no effect on Phayne's stats.
D-Link Ability Deck
- Talent Twirl
- Strike Raid
- Sonic Wave
- Poison Slash
- Arcanum Minor