Category:A.R. Worlds

The characters of Kamen Rider Decade exist amongst various iterations of reality within the series referred to as an A.R. World (Another Rider's / Alternate Reality World). The Nine Worlds (9つの世界) are the A.R. Worlds that are based on the previous entries of the Kamen Rider Series that have aired during the Heisei period of Japanese history. Each differs in some way from the series on which it was based. The New Worlds (新たな世界) are the A.R. Worlds that are not based on a previous entry of the Kamen Rider Series from the Heisei period.

A.R. Worlds
Originally, Tsukasa only knew that their destinations were nine A.R. Worlds to finish their journey. As the story progressed, they realized that their journey doesn't end at the ninth world, but further more towards new worlds, until Decade connects these worlds' stories through him. The A.R. worlds are alternate realities in Decade's point of view.

Nine Worlds

 * World of Kuuga (native world of Yusuke Onodera)
 * World of Kiva (native world of King Wataru and Kiva-la)
 * World of Ryuki (native world of Shinji Tatsumi)
 * World of Blade (native world of Kazuma Kendate)
 * World of Faiz (native world of Takumi Ogami)
 * World of Agito (native world of Shouichi Ashikawa)
 * World of Den-O (in the main universe- where the Taros are, and the originating home of the Kamen Riders, neighbors with World of Shinkenger)
 * World of Kabuto (native world of Souji)
 * World of Hibiki (native world of Master Asumu)

New Worlds

 * World of Negatives (native world of the Dark Riders)
 * World of Diend (native world of Daiki Kaito)
 * World of Shinkenger (in the main universe- where the Shinkengers and Super Sentai are, neighbors with World of Den-O)
 * World of Black RX (native world of an alternate (RX) Kotaro Minami)
 * World of Black (native world of an alternate (Black) Kotaro Minami)
 * World of Amazon (native world of an alternate Daisuke Yamamoto)
 * World of X-Rider (origin of Dai-Shocker's Apollo Geist)
 * World of Stronger (S.I.C. Hero Saga Kamen Rider Decade: World of Stronger)
 * World of the Rider War (the point of connection where the A.R. Worlds would merge, excluding World of Den-O and World of Shinkenger for being in the main universe's Earth)
 * World of OOO (native world of an alternate Eiji Hino)
 * World of Gaim (native world of the Armored Riders)

Other

 * World of G (native world of Goro)
 * World of Natsumi (native world of Natsumi Hikari and the Hikari Studio)
 * World of Decade (native world of Tsukasa Kadoya, despite having 'no story of his own')
 * World of Kamen Rider (native world of Ambassador Hell)
 * World of Televi-Kun (Special Adventure DVD)
 * World of Net (Net Movies)
 * World of alternate Kamen Rider Skull
 * World within the Magic Stone (referred to by Decade as the 'World of Wizard')
 * World of the Sengoku Period (native world of Bujin Riders)

Worlds with no relation to Decade

 * Magic Land - An alternate world in the Kamen Rider Wizard universe.
 * World of Soccer (or unofficially known as 'World of Gaim' created by Lapis where the alternate Gaim Riders compete in a Soccer tournament as opposed to Dancing, as well as freed from Inves invasions.)
 * World of Gamma - An alternate world in the Kamen Rider Ghost universe.
 * Island of Eyecons - A pocket world in Ghost.
 * Chou Super Hero Taisen World - An alternate world in Kamen Rider Ex-Aid.
 * World of Kyuranger - The world where Uchu Sentai Kyuuranger takes place.
 * The world where Kamen Rider Amazons takes place.
 * World of Build - The world where Kamen Rider Build takes place.

Novel
In the novel re-imagination of the Kamen Rider Decade TV series, Kamen Rider Decade: The World of Tsukasa Kadoya ~The Garden Inside the Lens~, the Nine Worlds are not alternate realities, but in fact the original worlds. The Hikari Studio group has already traveled to 6 different worlds when the novel begins, leaving only Den-O, Kuuga and Kabuto’s world unexplored.