List of Kamen Rider Decade characters
The characters of Kamen Rider Decade exist amongst various different iterations of reality within the series. Each reality is based on a previous entry of the Kamen Rider Series that have aired during the Heisei era of Japanese history.
Hikari Studio
The Hikari Studio (光写真館, Hikari Shashinkan) is the photography studio that the Hikari family owns and where Tsukasa Kadoya develops his photographs. The various paintings located in the studio allow it to transport its occupants to any of the other Kamen Riders' worlds. Its interior and exterior automatically transform to blend into the surroundings when moving across dimensions.
Tsukasa Kadoya
Tsukasa Kadoya (門矢 士, Kadoya Tsukasa) is a young arrogant man without any memory of his past. Being a photographer, his photos never come out right, later revealed to be a sign of his world being slowly destroyed by the convergence of the other Kamen Riders' worlds. To save his world, he transforms into Kamen Rider Decade (仮面ライダーディケイド, Kamen Raidā Dikeido).
Tsukasa Kadoya is portrayed by Masahiro Inoue (井上 正大, Inoue Masahiro).
Natsumi Hikari
Natsumi Hikari (光 夏海, Hikari Natsumi) is a young woman who works at the photo studio under her grandfather, nicknamed by Tsukasa as "Natsumikan" (夏蜜柑, Natsumikan). She also realizes the danger that their world is in, having nightmares of the Rider Army (ライダー軍, Raidā Gun) all destroyed by Decade. She finds Decade's belt and gives it to Tsukasa, but later decides to accompany him on his journey to prevent her dream from coming true. She occasionally keeps Tsukasa in line with the Hikari Family Secret Laughing Pressure Point (光家秘伝・笑いのツボ, Hikari-ke Hiden: Warai no Tsubo). She also appears to have feelings for Tsukasa, or at least cares for his well-being, which is hinted during her conversation with Yuusuke Onodera. Despite Narutaki's offer to save her, she refuses and chooses to see Decade's journey to the end.
Natsumi Hikari is portrayed by Kanna Mori (森 カンナ, Mori Kanna).
Eijiro Hikari
Eijiro Hikari (光 栄次郎, Hikari Eijirō) is the owner of the Hikari Studio and Natsumi's grandfather. When he discovers that his photo studio is the means of accessing the many other Kamen Riders' worlds by accident, he is not surprised but amused at the fact and is glad to assist Tsukasa in his mission. Whenever they arrive to a different world, he would cook a different meal each time.
Eijiro Hikari is portrayed by Renji Ishibashi (石橋 蓮司, Ishibashi Renji).
Narutaki
Narutaki (鳴滝) is a mysterious man who refers to himself as a prophet, and is protected by an aura that renders him immune to the convergence of the ten worlds. He also has the ability to move freely between the worlds and summon Riders from other worlds. He firmly believes that Decade should not exist in any world and tells the other Kamen Riders that Decade will destroy their world. He also desires to save Natsumi, offering her freedom while telling her that the Rider War will awaken Decade's true nature. After Decade defied his premonitions of doom in the previous nine worlds, Narutaki decides to personally deal with him in Hibiki's World, revealing to Natsumi that Tsukasa's actions are actually destroying the worlds rather than saving them as they were told.
Narutaki is portrayed by Tatsuhito Okuda (奥田 達士, Okuda Tatsuhito).
Daiki Kaito
Daiki Kaito (海東 大樹, Kaitō Daiki) is a mysterious young man who travels the Rider Worlds in hunt for their treasures as Kamen Rider Diend (仮面ライダーディエンド, Kamen Raidā Diendo), possessing the power to summon Riders to serve him. He seems to know more about Tsukasa than Tsukasa himself does. Narutaki is very fearful of Kamen Rider Diend, though he knows that he and Decade are incapable of coexistence.
Daiki Kaito is portrayed by Kimito Totani (戸谷 公人, Totani Kimito).
Kuuga's World
Kuuga's World (クウガの世界, Kūga no Sekai) is the version of reality where Kamen Rider Kuuga takes place. However, instead of Yuusuke Godai and other characters from the original series, others have taken their place. The painting used to arrive in this world shows a city with police cars and Mount Hitoki (灯溶山, Hitoki-yama) in the background.
Yuusuke Onodera
Yuusuke Onodera (小野寺 ユウスケ, Onodera Yūsuke) is a young man with a child-like personality who has the power to become Kamen Rider Kuuga (仮面ライダークウガ, Kamen Raidā Kūga). He later ends up traveling with the Hikari Studio.
Yuusuke Onodera is portrayed by Ryouta Murai (村井 良大, Murai Ryōta).
Ai Yashiro
Ai Yashiro (八代 藍, Yashiro Ai) is a detective and the leading operative of the police force formed to fight the Grongi. She mistakes Decade for "Unidentified Lifeform #10" (未確認生命体十号, Mikakunin Seimeitai Jūgō) after Decade kills Baberu. While investigating the lair of the Grongi to take out the resting Gamio, she and her group are overwhelmed by the miasma caused by the Grongi leader's revival. However, Yuusuke is not able to save her in time, as the poison she breathed in later killed her. Prior to her death, she makes Yuusuke promise that he will fight in order to protect everyone's smiles.
Ai Yashiro is portrayed by Hiroko Sato (佐藤 寛子, Satō Hiroko).
N-Gamio-Zeda
N-Gamio-Zeda (ン・ガミオ・ゼダ, N Gamio Zeda) is the king of the Grongi Tribe (グロンギ族, Gurongi Zoku) in Kamen Rider Decade, also called "The Ultimate Darkness" (究極の闇, Kyūkyoku no Yami). He refers to himself as otherworldly because he should have never been revived. He is sealed and the Grongi are attempting to unseal him with a Sacred Gegeru, targeting five police women without spilling blood to revive him. Though they obtain four kills, Tsukasa uses Ai as bait to lure the Grongi out and gives her a nose bleed to ruin the Gegeru. The effects of the distortion revive Gamio anyways, and he uses his power to convert every human corpse within his Miasmic aura into a Grongi. Although his ultimate goal is to have his sired Grongi kill each other, Gamio is destroyed by Kuuga and Decade performing a combo attack.
N-Gamio-Zeda is voiced by Fumihiko Tachiki (立木 文彦, Tachiki Fumihiko).
- Statistics:
- Height: 220cm
- Weight: 240kg
The Grongi
The Grongi Tribe (グロンギ族, Gurongi Zoku) are a mysterious, ancient civilization that can transform into monsters to kill people for their ruthless game, the "Gegeru". They are referred to by the police as Unidentified Life Forms (未確認生命体, Mikakunin Seimeitai) and are named in a "Group-Species-Creature type" order.
- Me-Gyarido-Gi (メ･ギャリド･ギ, Me Gyarido Gi, 1-2): A member of the Me Group, labeled Unidentified Life Form #7 (未確認生命体七号, Mikakunin Seimeitai Nanagō). He battles Kuuga and is killed by his Dragon Form's Splash Dragon attack.
- Ra-Dorudo-Gu (ラ･ドルド･グ, Ra Dorudo Gu, 1-2): A member of the Ra-Group, the judges of the Gegeru, labeled Unidentified Life Form #8 (未確認生命体八号, Mikakunin Seimeitai Hachigō). He fights Kuuga and attempts to flee before being killed by Kuuga who uses Pegasus Form's Blast Pegasus attack.
- Go-Baberu-Da (ゴ･バベル･ダ, Go Baberu Da, 2): Labeled "Unidentified Life Form #9" (未確認生命体九号, Mikakunin Seimeitai Kyūgō), Baberu is forced by Decade to reveal the nature of the Gegeru before being killed by Decade's Dimension Kick.
- Go-Bemiu-Gi (ゴ･ベミウ･ギ, Go Bemiu Gi, 2): A female Grongi overseeing Gamio's revival, she is killed by Decade.
- Me-Biran-Gi (メ･ビラン･ギ, Me Biran Gi, 2): One of the leading Grongi overseeing Gamio's revival. He is killed by Kuuga's Mighty Kick when he attempts to intervene in the battle between Kuuga and Decade.
N-Gamio-Zeda is able to create various Grongi from human corpses using his miasma, but some are later absorbed by him in a last effort to defeat Kuuga and Decade. The remaining Grongi died after Gamio is defeated.
Kiva's World
Kiva's World (キバの世界, Kiba no Sekai) is the version of reality where Kamen Rider Kiva takes place. Unlike the original series, this world allows Fangires and humans to coexist, with the King's servants destroying the rebellious Fangires. The painting that allows entry into Kiva's World depicts a nighttime cityscape with Castle Doran emerging from a building.
Wataru
Wataru (ワタル, Wataru) is a twelve-year-old half-Fangire boy who is referred to as the Prince (王子, Ōji). However, he is reluctant to claim the title of King (キング, Kingu) of the Fangires. Like his namesake in Kiva, Wataru has the ability to transform into Kamen Rider Kiva (仮面ライダーキバ, Kamen Raidā Kiba) with the aid of Kivat.
Wataru is portrayed by Arashi Fukasawa (深澤 嵐, Fukasawa Arashi).
Kivat-bat the 3rd
Kivat-bat the 3rd (キバットバットⅢ世, Kibattobatto Sansei) is the third generation of the Kivat-bat Family (キバットバット家, Kibattobatto Ke). He formed a partnership with Wataru to give him the power of Kiva, attaching to the Kivat Belt (キバットベルト, Kibatto Beruto) to allow his human partner to transform and use other abilities through the Fuestles.
Tomokazu Sugita (杉田 智和, Sugita Tomokazu) reprises his role voicing Kivat-bat the 3rd.
Kivala
A white-colored female Kivat, Kivala (キバーラ, Kibāra) is the younger sister of Kivat. She is extremely tiny, small enough to be hidden in an adult's closed fist. She learns of Decade from Narutaki, and uses her power to bring Yuusuke into her world, and then sends Tsukasa into another to do battle with Kaixa. She later ends up traveling with the Hikari Studio, though remaining in contact with Narutaki with only Natsumi aware of it. She seems to like Yuusuke the most out of the traveling group as she is delighted when he returns to travel with them after they leave Agito's World.
Kivala is voiced by Miyuki Sawashiro (沢城みゆき, Sawashiro Miyuki).
- Wingspan: 11.5cm
- Weight: 230g
- Max. flight speed: 70km/h
Arms Monsters
The Arms Monsters (アームズモンスター, Āmuzu Monsutā) are servants of Kiva, each the last of his kind. Composed of Garulu (ガルル, Garuru) of the Wolfen Race (ウルフェン族, Urufen Zoku), Basshaa (バッシャー, Basshā) of the Merman Race (マーマン族, Māman Zoku), and Dogga (ドッガ, Dogga) of the Franken Race (フランケン族, Furanken Zoku), they support Kiva by turning into the weapons that allow Kiva to change form. They are absorbed into Beetle Fangire's breast plate and shoulder armor when they question their new king's intentions of removing the human/Fangire coexistence law.
Isshin Chiba (千葉 一伸, Chiba Isshin), Kōki Miyata (宮田 幸季, Miyata Kōki), and Takaya Kuroda (黒田 崇矢, Kuroda Takaya), voice Garulu, Basshaa, and Dogga, respectively.
Beetle Fangire
The previous King of the Fangire Race, the Beetle Fangire (ビートルファンガイア, Bītoru Fangaia) was exiled for loving a human woman who gave birth to his half-breed successor, Wataru. Making himself see the coexistence and peace between the two races as nothing more than a farce for his son's sake, the Beetle Fangire breaks the peace by attacking humans to gather their Life Energy and reclaim his title, even stealing Kivat from Wataru. His actions of removing the law to restart past conflicts between the two races provide the motivation for Wataru to step up and truly claim his place as King of the Fangires. In the end, he is weakened by Decade's Kiva Arrow, then fatally wounded by a Dimension Kick/Darkness Moon Break combo. Revealing that he knew of the Fangire's true identity and intent before he dies, Tsukasa plays a final song for him before the man shatters.
The Beetle Fangire and his human form are played by Mansaku Ikeuchi (池内 万作, Ikeuchi Mansaku).
- Statistics
- True Name: Attonement of the Garden Divided, the International Dateline (贖罪の園を分断する、日付変更線, Shokuzai no Sono o Bundan suru, Hizukehenkōsen)
- Tribe: Insect Class (インセクトクラス, Insekuto Kurasu)
- Height: 225cm
- Weight: 230kg
The Fangires
The Fangire Race (ファンガイア族, Fangaia Zoku) are vampiric creatures that resemble stained glass, originally feeding off of the Life Energy (ライフエナジー, Raifu Enajī) of humans until they are commanded by their king to coexist with them. However, some of these Fangires are unable to follow this law due to their instincts. Each Fangire belongs to a specific class based on the animal form it takes. Several Fangires also appear in the first episode when Natsumi is trapped within the changing dimensions. They include the Shark, Moose, Horsefly, Rat, Mantis, and Seamoon Fangires. The Mantis Fangire later appears fighting the Beetle Fangire.
- Ryo Itoya/Spider Fangire (糸矢 僚／スパイダーファンガイア, Itoya Ryō/Supaidā Fangaia, 4): The first Fangire Tsukasa and Natsumi encounter in Kiva's World. He reveals to them the truce between the humans and Fangires. Sohto (創斗, Sōto) reprises his role as the Spider Fangire.
- Swallowtail Fangire (スワローテイルファンガイア, Suwarōteiru Fangaia, 4-5): A Fangire with the title of Bishop (ビショップ, Bishoppu), his task is to oversee the progress of all Fangires and their moral conduct, deeming those who are traitors to their king's laws. When the Beetle Fangire regained his title, the Swallowtail Fangire aided his master until he is shattered by Decade's Dimension Slash. The Swallowtail Fangire is voiced by Tomohiro Tsuboi (坪井 智浩, Tsuboi Tomohiro).
- Lion Fangire (ライオンファンガイア, Raion Fangaia, 4): A Fangire with the title of Rook (ルーク, Rūku), he is chasing after a renegade Fangire when Tsukasa interferes and kills him with the Ride Booker's Decade Slash. The Lion Fangire is voiced by Toshitsugu Takashina (高階 俊嗣, Takashina Toshitsugu).
Ryuki's World
Ryuki's World (龍騎の世界, Ryūki no Sekai) is the version of reality where Kamen Rider Ryuki takes place. In this world, there exists the Kamen Rider Trial (仮面ライダー裁判, Kamen Raidā Saiban), a battle where the Kamen Riders fight each other within a parallel dimension known as the Mirror World (ミラーワールド, Mirā Wārudo) alongside their Contract Monsters (契約モンスター, Keiyaku Monsutā) in order for the victor to decide the fate of a defendant in a criminal case. Though no harm occurs to the Rider while in the Mirror World, a battle in the real world can be fatal and use of Vent cards outside a battle is forbidden. The painting used to arrive in this world shows the Dragredder flying within the Mirror World as shown in the mirrored windows of a skyscraper.
Shinji Tatsumi
Shinji Tatsumi (辰巳 シンジ, Tatsumi Shinji) is a young cameraman who works for the Atashi Journal, a popular magazine that covers the Kamen Riders and the trials. When the editor of the journal is murdered, Shinji becomes a Kamen Rider to decide the fate of the suspect. Like his namesake in Ryuki, Shinji has the ability to transform into Kamen Rider Ryuki (仮面ライダー龍騎, Kamen Raidā Ryūki) and use the power of his Contract Monster Dragreder.
Shinji Tatsumi is portrayed by Momosuke Mizutani (水谷 百輔, Mizutani Momosuke).
Ren Haguro
Ren Haguro (羽黒 レン, Haguro Ren) is a former journalist of the Atashi Journal and Shinji's former best friend, mysteriously leaving the group three years ago without explanation. Like his namesake in Ryuki, Ren has the ability to transform into Kamen Rider Knight (仮面ライダーナイト, Kamen Raidā Naito) and use the power of his Contract Monster Darkwing. When Reiko is murdered, Ren enters the Trial to find the Rider who possesses the Time Vent Card. After defeating Scissors, Ren encounters Decade in a brief confrontation before Zolda intervenes. Later while forced to fight Shinji who accuses him of playing a part in Reiko's death, Decade's fight with Imperer stops theirs. Soon after, Decade battles Knight with the former being the superior fighter until Abyss intervenes. After defeating Odin, Ren acquires the Time Vent card at the cost of being too injured to use it himself.
Ren Haguro is portrayed by Eiki Kitamura (北村 栄基, Kitamura Eiki).
Reiko Momoi
Reiko Momoi (桃井 玲子, Momoi Reiko) is the editor of the Atashi Journal. When Natsumi finds her upon arriving in Ryuki's World, Reiko mysteriously dies, leaving Natsumi as the sole suspect of her murder. However, Ryuki uses the Time Vent Card to alter time and save her, while simultaneously revealing the true murderer.
Reiko Momoi is portrayed by Sae Takahashi (高橋 佐衣, Takahashi Sae).
Kamata
Kamata (鎌田) is a mysterious man who is the sub-chief editor of the Atashi Journal. In Ryuki's World, he has the ability to transform into Kamen Rider Abyss (仮面ライダーアビス, Kamen Raidā Abisu) with his Contract Monsters Abysslasher and Abysshammer. Once exposed as the one behind Reiko's murder and as an Undead, Narutaki returns Kamata to his homeworld: Blade's World.
Kamata is portrayed by Masato Irie (入江 雅人, Irie Masato).
Other Kamen Riders
Other than Kamen Rider Raia (仮面ライダーライア, Kamen Raidā Raia), Kamen Rider Gai (仮面ライダーガイ, Kamen Raidā Gai), and Kamen Rider Femme (仮面ライダーファム, Kamen Raidā Famu), the following Riders are seen in the Battle Trial for the murder of Reiko Momoi.
- Kamen Rider Scissors (仮面ライダーシザース, Kamen Raidā Shizāsu, 6): Scissors is a cheating Rider who uses the power of his Contract Monster Volcancer, labeled by the Journal to have a victory rate of 6.8%. He is removed from the trial by Knight. Kamen Rider Scissors is voiced by Yasunori Masutani (増谷 康紀, Masutani Yasunori).
- Kamen Rider Zolda (仮面ライダーゾルダ, Kamen Raidā Zoruda, 6): A public prosecutor who sees Natsumi guilty, Zolda is a Rider who uses the power of his Contract Monster Magnugiga.
- Kamen Rider Verde (仮面ライダーベルデ, Kamen Raidā Berude, 6): Verde is a Rider who uses the power of his Contract Monster Biogreeza. He lowers his guard when falling for Scissors' trap and is removed from the trial by Volcancer.
- Kamen Rider Tiger (仮面ライダータイガ, Kamen Raidā Taiga}, 6): Tiger is a Rider who uses the power of his Contract Monster Destwilder. He is removed from the trial by Zolda's Giga Launcher.
- Kamen Rider Imperer (仮面ライダーインペラー, Kamen Raidā Inperā, 6): Imperer is a Rider who uses the power of his Contract Monsters Gigazelle, Megazelle, Omegazelle, Negazelle, & Magazelle. He is removed from the trial by Decade.
- Kamen Rider Odin (仮面ライダーオーディン, Kamen Raidā Ōdin, 7): Odin is a Rider who uses the power of his Contract Monster Goldphoenix. He lets himself be removed from the trial by Knight's Final Vent, allowing Knight to take the Time Vent Card.
Blade's World
Blade's World (ブレイドの世界, Bureido no Sekai) is the version of reality where Kamen Rider Blade takes place. In this world, the Riders are high rank employees of the BOARD Corporation (株式会社BOARD, Kabushikigaisha Bōdo), and are effectively "Kamen Rider Salarymen" (仮面ライダーサラリーマン, Kamen Raidā Sararīman), whose job it is to combat the Undead once receiving clearance to use Rouzers. In BOARD, there is a ranking system with Ace (エース, Ēsu) at the top followed by King, Queen, Jack, and the numbers with Two at the bottom. The painting used to arrive in this world shows a hand of facedown Rouse cards with the Ace of Spades (Blade's Change Beetle) face up.
Kazuma Kendate
Kazuma Kendate (剣立 カズマ, Kendate Kazuma) is a Rank Ace employee of BOARD who has the ability to transform into Kamen Rider Blade (仮面ライダーブレイド, Kamen Raidā Bureido) with the sealed Beetle Undead. Before Tsukasa arrives in Blade's World, Kazuma believes himself to be invincible.
Kazuma Kendate is portrayed by Hiroki Suzuki (鈴木 拡樹, Suzuki Hiroki).
Sakuya Hishigata
Sakuya Hishigata (菱形 サクヤ, Hishigata Sakuya) is a Rank Ace senior employee of BOARD who has the ability to transform into Kamen Rider Garren (仮面ライダーギャレン, Kamen Raidā Gyaren) with the sealed Stag Undead. After Kazuma's demotion, he start treating him badly, until it is revealed that he did so to test Kazuma. He then is drained of his life energy by Hajime to create the Joker card.
Sakuya Hishigata is portrayed by Yoshihiko Narimatsu (成松 慶彦, Narimatsu Yoshihiko).
Mutsuki Kuroba
Mutsuki Kuroba (黒葉 ムツキ, Kuroba Mutsuki) is an employee of BOARD a Rank King recently promoted to an Ace who has the ability to transform into Kamen Rider Leangle (仮面ライダーレンゲル, Kamen Raidā Rengeru) with the sealed Spider Undead. After he is promoted to Ace and Kazuma is demoted, he starts treating him badly, until it is revealed that he did so to test Kazuma, while also pretending he gained a superiority complex. Mutsuki is the last Rider to lose his Rider System along with Hishigata, learning of Chalice's true identity as he and Hishigata are drained of their life energy by Hajime to create the Joker card.
Mutsuki Kuroba is portrayed by Kazuma Kawahara (川原 一馬, Kawahara Kazuma).
Hajime Shijo
Hajime Shijo (四条 ハジメ, Shijō Hajime) is the president of the BOARD Corporation who secretly uses the sealed Mantis Undead to assume the form of the legendary Kamen Rider Chalice (仮面ライダーカリス, Kamen Raidā Karisu). Because he is more interested in business ethnics, Hajime sees himself as the only thing keeping BOARD alive by offering his company's aid once paid by the government. Furthermore, he conspires with Kamata by taking the other Rider Systems to begin a joint plan to take over the world by creating the Joker card from the DNA of all four Ace Undead. Being unable to get Kazuma to give him the Blay Buckle by normal means, Chalice makes his presence known during Decade and Blade's fights against the Paradoxa Undead and the other BOARD Riders, stripping Kazuma of his Blay Buckle before fighting Decade until Todoroki's sudden appearance. But Hajime escapes with the Garren Buckle as well, later taking the Leangle Buckle with his identity exposed to Hishigata and Mutsuki whom he adbucts and sacrifices to complete the Joker card. Assuming the form of the Joker (ジョーカー, Jōkā), Hajime meets his end at the hands of Blade and Decade.
Hajime Shijo is portrayed by Ruo (累央).
Kitchen Staff
Ai (アイ, Ai), Mai (マイ, Mai) and Mi (ミー, Mī) are Rank 8 employees of BOARD, serving under Tsukasa as the kitchen staff in preparing the food for the higher ups.
Rumi Hiiragi (柊 瑠美, Hiiragi Rumi), Yuka Kayama (香山 裕香, Kayama Yuka), and Ayano Washizu (鷲巣 あやの, Washizu Ayano) play Ai, Mai, and Mi, respectively.
Paradoxa Undead
The Paradoxa Undead (パラドキサアンデッド, Paradokisa Andeddo) is a Category King Undead able to create a blade-like wind from his forearm to kill his target. Normally, he is disguised as a man named Kamata (鎌田). After being exposed in Ryuki's World, Kamata returns to Blade's World where he works with Hajime in a plot to take over the world as the chairman of the BOARD Corporation. After helping Hajime steal the three other Rider Systems, Kamata helps him create the Joker Rouse Card. He is later defeated alongside the Joker by Decade and Blade.
Masato Irie continues to portray Kamata and provides the voice the Paradoxa Undead in the Blade's World arc. In the music video for "Journey through the Decade", Gackt summons the Paradoxa Undead to fight Tsukasa.
- Statistics
- Deck: King of Hearts
- Height: 227cm
- Weight: 127kg
The Undead
The Undead (アンデッド, Andeddo) are a race of monsters that are accidentally released from their seals and go on a rampage. Among them, there are several specialized Undead: Category Aces, the Royal Club, and the Joker. Several Undead also appear in the first episode when Natsumi is trapped within the changing dimensions. They include the Lizard, Pecker, Squid, and Caucasus Undead.
- Buffalo Undead (バッファローアンデッド, Baffarō Andeddo, 8): A Category 8 Undead, he terrorizes humans until Kazuma and Hishigata confront him before receiving clearance to transform into Blade and Garren. In the end, the Buffalo Undead is defeated by Blade's Lightning Blast before being sealed into the Magnet Buffalo card.
- Elephant Undead (エレファントアンデッド, Erefanto Andeddo, 8): A Category Jack Undead, he is destroyed by Decade using Ryuki's Strike Vent.
- Capricorn Undead (カプリコーンアンデッド, Kapurikōn Andeddo, 8): A Category Queen Undead, he aids the Paradoxa Undead until he is destroyed by Decade's Dimensional Kick.
Faiz's World
Faiz's World (ファイズの世界, Faizu no Sekai) is the version of reality where Kamen Rider 555 takes place. In this world, students of the Smart Brain High School (スマートブレイン･ハイスクール, Smāto Burēn Hai Sukūru) are being attacked nightly by monsters known as the Orphnoch. The painting used to enter Faiz's World is a splitscreen featuring the Autovajin in Battle Mode and blue butterflies, referencing Smart Lady, a character from the original series who was Smart Brain Corporation's mascot of sorts.
Takumi Ogami
Takumi Ogami (尾上 タクミ, Ogami Takumi) is a hot-blooded boy who protects Smart Brain High from the Orphnoch, his reason for it is a mystery. Like his namesake in 555, Takumi has the ability to transform into Kamen Rider Faiz (仮面ライダーファイズ, Kamen Raidā Faizu) through the use of the Faiz Gear along with assuming the form of the Wolf Orphnoch (ウルフオルフェノク, Urufu Orufenoku), liked Takumi Inui from original 555.
Takumi Ogami is portrayed by Syunsuke Seino (制野 峻右, Seino Shunsuke).
Yuri Tomoda
Yuri Tomoda (友田 由里, Tomoda Yuri) is one of Takumi's fellow students, member of Smart Brain High's photography club with a dream to create the perfect photo journal. She is not as good-willed as she initially appears, expressing being prejudiced to the Orphnoch as well as believing Faiz to be an urban legend. However, when targeted by the Lucky Clover members, Yuri learns of Takumi's true nature. The situation leaves her confused until she sees Takumi attempt to protect her camera, hearing his reason for becoming Faiz. After the fight, Yuri convinces Takumi to keep protecting Smart Brain High to protect her dream.
Yuri Tomoda is portrayed by Yurie Midori (緑 友利恵, Midori Yurie).
Momose
Momose (百瀬) is a student of Smart Brain High who is a member of the Lucky Clover (ラッキークローバー, Rakkī Kurōbā): a group of top-ranked students who are actually Orphnoch. Momose's true form is that of the Tiger Orphnoch (タイガーオルフェノク, Taigā Orufenoku), possessing the power to revive Orphnochs on the verge of death. After learning the truth behind Faiz, Momose decides to take over the school and sire new Orphnoch from the student body. However, the Riders intervene and the Tiger Orphnoch is killed by Decade's Decade Photon.
Momose is portrayed by Ryosuke Miura (三浦 涼介, Miura Ryōsuke).
- Statistics:
- Height: 220cm
- Weight: 140kg
Orphnoch
The Orphnoch (オルフェノク, Orufenoku) are humans who have entered the next stage in evolution, possessing heighten physical and other various special abilities. Several Orphnoch appear in the first episode where Decade assumes Faiz's form to fight them off. They include the Octopus, Okra, Pigeon, Dolphin and Rhinoceros Beetle Orphnoch.
- Butterfly Orphnoch (バタフライオルフェノク, Batafurai Orufenoku, 10): Unable to become a student at Smart Brain High, she attacks a security officer until Faiz arrives and kills her with his Sparkle Cut attack. Butterfly Orphnoch is portrayed by Riho Okada (岡田 里穂, Okada Riho).
- Shukawa/Lobster Orphnoch (朱川／ロブスターオルフェノク, Shukawa/Robusutā Orufenoku, 10-11): The only female member of Lucky Clover. Though she was ressurected by the Tiger Orphnoch, she met her end against Decade's Decade Photon. Shukawa is portrayed by Ayasa Hanagata (花形 綾沙, Hanagata Ayasa).
- Genda/Dragon Orphnoch (玄田／ドラゴンオルフェノク, Genda/Doragon Orufenoku, 10-11): A jock member of Lucky Clover who is destroyed by Decade as Blade until the Tiger Orphnoch arrives and resurrects him into his muscular Majin Form. He is destroyed for good by Decade's Decade Photon. Genda is portrayed by CHIKARA.
- Shirogane/Centipede Orphnoch (城金／センチピードオルフェノク, Shirogane/Senchipīdo Orufenoku, 10): A booksmart member of Lucky Clover who is killed by Diend's Dimension Shot while attempting to steal the Faiz Belt. Shirogane is portrayed by Takuya Nagaoka (永岡 卓也, Nagaoka Takuya).
Agito's World
Agito's World (アギトの世界, Agito no Sekai) is the version of reality where Kamen Rider Agito takes place. Similar to Kuuga's World, the Riders and the police battle the Grongi. However, a new evil surfaced onto the world, monsters that they referred to as the Unknown. The painting used to enter Agito's World is the elaborate tapestry seen in the opening sequence of Agito that depicts the story of Agito and the Unknown. This story arc further expands on the war between the Unknown and the Grongi, which is hinted in both their respective series and explained more outside them.
Shouichi Ashikawa
Shouichi Ashikawa (芦河 ショウイチ, Ashikawa Shōichi) is a young man who supports the police, originally the user of the G3 system until he mysteriously disappeared. In reality, Shouichi left because he began to transform into Kamen Rider Exceed Gills (仮面ライダーエクシードギルス, Kamen Raidā Ekushīdo Girusu), a partially evolved creature that is targeted by the Unknown. By the time the Unknown begin their attack, with Yuusuke's help, Shouichi completes his metamorphisis into the evolutionary Kamen Rider Agito (仮面ライダーアギト, Kamen Raidā Agito).
Shouichi Ashikawa is portrayed by Satoshi Yamanaka (山中 聡, Yamanaka Satoshi), previously Kamen Rider Kirameki in Kamen Rider Hibiki & The Seven Fighting Demons.
Toko Yashiro
Toko Yashiro (八代 淘子, Yashiro Tōko), resembling Ai Yashiro of Kuuga's World, is a scientist and the creator of the G-Series of Kamen Riders. Compared to Ai, Toko is more high-strung and sees the G3-X Suit as humanity's only hope. Toko also has some feelings towards Shouichi as Ai had for Yuusuke, which was her motivation for building the G3-X suit. She monitors the condition of the operator and the G3 suit during combat from the G-Trailer mobile command base.
Hiroko Sato returns to portray Toko Yashiro in the Agito's World arc.
Taurus Ballista
Taurus Ballista (タウルス・バリスタ, Taurusu Barisuta), the Buffalo Lord (バッファローロード, Baffarō Rōdo), is one of the stronger Lords, armed with the Supremacy Torreana (至高のトリアンナ, Shikō no Torianna). Ballista embodies the Lords' purpose is to purge the world of any above average human for their own good. However, Tsukasa tells him that they do not need someone to protect humans as the Lord is destroyed by the teamwork of Decade, Agito, and Yuusuke in the G3-X armor.
Taurus Ballista is voiced by Kōsuke Toriumi (鳥海 浩輔, Toriumi Kōsuke).
- Statistics:
- Height: 222cm
- Weight: 172kg
Lords
The Lords (ロード, Rōdo) are a group of powerful animal-headed disciples with a wing-shaped protuberance sticking out of their shoulders. They are referred by the police department as the Unknown (アンノウン, Annōn) and target any humans with abilities above normal or any threat to humanity, deeming themselves as humanity's holy protectors.
- Formica Pedes (フォルミカ・ペデス, Forumika Pedesu, 12-13): Ant Lord (アントロード, Anto Rōdo) soldiers who serve Ballista and Regia.
- Formica Regia (フォルミカ・レギア, Forumika Regia, 13): The Queen Ant Lord and Ballista's right hand, aiding him until she died taking Agito's Rider Kick which was meant for her master. Formica Regia is voiced by Natsuki Mori (森 夏姫, Mori Natsuki).
The Grongi
Though Agito's World has it own members of the Grongi Tribe (グロンギ族, Gurongi Zoku), they are practically replaced by the surfacing of the Lords.
- Me-Bajisu-Ba (メ･バヂス･バ, Me Bajisu Ba, 12): Labeled Unidentified Life Form #47, this Me Group member battles the police until he is blasted to bits by G3X's Cerberus.
- Zu-Mebio-Da (ズ･メビオ･ダ, Zu Mebio Da, 12): Labeled Unidentified Life Form #48 (未確認生命体四十八号, Mikakunin Seimeitai Yonjūhachigō), a female member of the Zu Group that appears in Agito's World. She is murdered by two Ant Lords as she attempts to escape from Diend.
- Me-Ginoga-De (メ･ギノガ･デ, Me Ginoga De, 12): Labeled Unidentified Life Form #49 (未確認生命体四十九号, Mikakunin Seimeitai Yonjūkyūgō), a member of the Me Group that appears in Agito's World. He is killed by the teamwork of Diend and the summoned Drake and Delta.
Den-O's World
Den-O's World (電王の世界, Den'ō no Sekai) is the version of reality in which Kamen Rider Den-O takes place. Unlike the other Riders' Worlds, Den-O's World is almost identical to the setting of the original series. The only difference is the interior of the DenLiner having changed to that of the NEW DenLiner. The painting used to enter this world depicts the DenLiner moving across the sands of time, which Ryutaros doodles on later in the episode arc. The Den-O's World arc coincides with the theatrical release of Cho Kamen Rider Den-O & Decade NEO Generations: The Onigashima Battleship, which takes place within the continuity of Decade like Kamen Rider Den-O: I'm Born! did with Den-O.
Momotaros
Momotaros (モモタロス, Momotarosu) is a hot-blooded Imagin among the DenLiner gang who uses a sword named the Momotarosword (モモタロスォード, Momotaroswōdo). Due to the actions of the Oni Brothers in the past, Momotaros loses his sense of self unable to retain his physical form outside the DenLiner, forcing him to use Tsukasa and Yuusuke as host bodies to fight the Imagin as Kamen Rider Den-O in Sword Form. After fighting the Alligator Imagin and regaining his form, Momotaros returns to the DenLiner and is welcomed back by the DenLiner gang before the young Ryotaro and Kotaro appear to inform him and the others of the Oni Brothers' part in the world's distortion. He disappeared along with the other Taros, finding himself on Onigashima as part of the Oni Conquest legend.
Toshihiko Seki (関 俊彦, Seki Toshihiko) reprises his role voicing Momotaros.
The Tarōs
These three Imagin, collectively known as the Tarōs with Momotaros, each give Den-O their power when they are called upon with each form suiting to their fighting style. They are composed of the smooth-talking Urataros (ウラタロス, Uratarosu), the noble Kintaros (キンタロス, Kintaros), and the childish Ryutaros (リュウタロス, Ryūtarosu). Warned of Decade's appearance and believing him to be the one who disrupted their world, the three possess Natsumi to fight him in their respective Den-O forms before the fight ends in a stalemate. After mysteriously disappearing, the three later support Decade and company during the events at Onigashima by possessing three Kamen Riders that Diend summons through the KamenRide Cards.
Kōji Yusa (遊佐 浩二, Yusa Kōji), Masaki Terasoma (てらそま まさき, Terasoma Masaki), and Kenichi Suzumura (鈴村 健一, Suzumura Ken'ichi) reprise their roles voicing their respective Tarōs.
Sieg
Sieg (ジーク, Jīku) is a swan-based Imagin with an ego who occasionally aids the DenLiner gang, providing Den-O the ability to become Wing Form. Though the crisis of Den-O's World is solved, Sieg appears in Hikari Studio in Kabuto's World in the possession of a manuscript of the Onigashima Conquest legend.
Shin-ichiro Miki (三木 眞一郎, Miki Shin'ichirō) reprises his role voicing Sieg.
Kohana
Kohana (コハナ, Kohana) is a little girl who lives on the DenLiner, her timeline having been erased from existence due to the Imagin going into the past. She can only exist because she is a Singularity Point, and not tied to the changes of time. She is the daughter of Yuto Sakurai and Airi Nogami, and the niece of Ryotaro Nogami.
Tamaki Matsumoto (松元 環季, Matsumoto Tamaki) reprises her role as Kohana.
Naomi
Naomi (ナオミ, Naomi) is the waitress of the DenLiner, known for her coffee that no Imagin can resist.
Rina Akiyama (秋山 莉奈, Akiyama Rina) reprises her role as Naomi.
Owner
The Owner (オーナー, Ōnā) of the DenLiner is a mysterious man with a habit of speaking in complexes when it comes to the nature of time. Owner enjoys eating various dishes that have a flag placed in the middle of them, aiming to eat his entire meal (usually rice or flan) without knocking the flags over.
Kenjirō Ishimaru (石丸 謙二郎, Ishimaru Kenjirō) reprises his role as the Owner.
Kotaro Nogami
Kotaro Nogami (野上 幸太郎, Nogami Kōtarō) is the young man from the future who can transform into Kamen Rider NEW Den-O (仮面ライダーＮＥＷ電王, Kamen Raidā Nyū Den'ō).
Dori Sakurada (桜田 通, Sakurada Dori) reprises his role as Kotaro Nogami from Saraba Kamen Rider Den-O: Final Countdown.
Ryotaro Nogami
Ryotaro Nogami (野上 良太郎, Nogami Ryōtarō) is the original Kamen Rider Den-O (仮面ライダー電王, Kamen Raidā Den'ō). However, the version that appears in Decade and The Onigashima Battleship is the younger incarnation of Ryotaro who was brought to the present to help the DenLiner gang against chaos about to be caused by the Oni Brothers.
Takuya Mizoguchi (溝口 琢矢, Mizoguchi Takuya) reprises his role as the younger Ryotaro Nogami from Kamen Rider Den-O: I'm Born!.
Silvra
One of the two Oni Brothers of Onigashima, Silvra (シルバラ, Shirubara) and is armed with a kanabō as his weapon. He briefly appears during Den-O Ax Form's fight with Decade to acquire a vase for his brother Kuchihiko's agenda. Though ignored at the time, it would later turn out he is one of the true culprits behind the chaos in Den-O's World.
Gelnewts
Gelnewts (ゲルニュート, Gerunyūto) are the Oni Brothers' Mirror Monster foot soldiers, armed with giant shurikens that are mounted on their backs when not in use. They accompanied Mimihiko in acquiring the vase for their masters' agenda.
Alligator Imagin
The Alligator Imagin (アリゲーターイマジン, Arigētā Imajin) is an Imagin who enacts his own scheme to change the past. Unlike other Imagin, the Alligator Imagin goes through a multitude of hosts to enact his scheme. Arriving in the past via a child, the Alligator Imagin proceeds to change the future and overpowers Decade and Den-O, taking the latter's DenGasher as his own. Diend and his KamenRide Card summoned Riotroopers allow for Den-O and Decade to regroup, and allow for Decade to get the Den-O Cards. With both Kuuga and Den-O, Decade destroys the Alligator Imagin with the Den-O Final AttackRide.
The Alligator Imagin is voiced by Kenta Miyake (三宅 健太, Miyake Kenta).
- Statistics
- Myth/legend: The Fox and the Crocodile (キツネとワニ, Kitsune to Wani)
- Height: 201cm
- Weight: 142kg
- Host: various
- Past date: December 30 2008
Imagin
The Imagin (イマジン, Imajin) are the creatures that arrive from the future to alter the past with only a handful standing against them. Several Imagin appear in the first episode when Natsumi is trapped in shifting dimensions attempting to get her to tell them her wish. These include the Spider, Bat, Molech, Bloodsucker and Whale Imagin.
- NEW Mole Imagin (ＮＥＷモールイマジン, Nyū Mōru Imajin, 14-15): The Alligator Imagin's Imagin minions who appear throughout Den-O's World. One is destroyed by Tsukasa as Den-O Sword Form. A few appear during Decade's fight with the other three forms of Den-O while Silvra and his minions steal a vase.
Kabuto's World
Kabuto's World (カブトの世界, Kabuto no Sekai) is the version of reality where Kamen Rider Kabuto takes place. The painting used to enter this world depicts Tokyo Tower with an arm outstretched in homage to Souji Tendou's "walking the path to heaven" pose.
Souji
Souji (ソウジ, Sōji) is a young man who has been given access to ZECT's technology, using the Kabuto Zecter to transform into Kamen Rider Kabuto (仮面ライダーカブト, Kamen Raidā Kabuto). However, Kabuto's Clock Up System malfunctioned, prompting ZECT to deem him a threat.
Souji is portrayed by Daijiro Kawaoka (川岡 大次郎, Kawaoka Daijirō).
Arata
Arata (アラタ, Arata) is an agent of ZECT under Otogiri who uses the Gatack Zecter to transform into Kamen Rider Gatack (仮面ライダーガタック, Kamen Raidā Gatakku). He was the only member of Otogiri's group to support Kabuto and attemps to defend him. But when he see Otogiri with Mayu, he attempts reason before he was attacked by ZECT Troopers, escaping them to call Tsukasa and the others for help as he learns that he and ZECT were being played by Otogiri.
Arata is portrayed by Tetsuya Makita (牧田 哲也, Makita Tetsuya).
Grandma
The elderly woman known only as Grandma (おばあちゃん, Obaachan) is very tenacious and gives out advice to her granddaughter Mayu, despite her grandson having disappeared. Following monk-like philosophies of peace and spouting amazingly appropriate zen-like phrases, she runs the Heaven House (天堂屋, Tendōya) oden restaurant. It is later revealed that she is aware of her grandaughter being a Worm during her conversation with Tsukasa, and her grandson being Kabuto as she expressed her worries when ZECT finished building the Clock Down system.
Grandma is portrayed by Sumie Sasaki (佐々木 すみ江, Sasaki Sumie).
Mayu
Mayu (マユ, Mayu) is the granddaughter of Grandma with a grudge against Kabuto for what she thought was brother's murder, only to later learn her 'brother' was actually a Worm. She is eventually revealed to be the Sisyra Worm (シシーラワーム, Shishīra Wāmu), targeted by the other Worms because of because of her ties to Kabuto.
Mayu is portrayed by Rio Kanno (菅野 莉央, Kanno Rio).
Phylloxera Worm
A Worm that assumed the form of Souji before losing his eye to him as Kabuto, the Phylloxera Worm assumed the alias of Sou Otogiri (弟切 ソウ, Otogiri Sō), becoming head agent of ZECT and user of TheBee Zecter to transform into Kamen Rider TheBee (仮面ライダーザビー, Kamen Raidā Zabī) to get his revenge on Souji. The fact that he resembled Souji had Mayu confuse him to be her brother before he revealed his true form while carrying out the Kabuto Capture Plan to get his revenge while ensuring that the Worms gain the adventage over the ZECT Rider. He was killed by Kabuto's & Decade's Rider Kick as they tear down the Clock Down broadcast tower in the process.
The Phylloxera Worm originally appeared in the SmaSTATION special Kamen Rider G in which Decade and the other Heisei Kamen Riders make a cameo appearance at the end.
Sou Otogiri is portrayed by Daijiro Kawaoka, who also portrayed Souji, while his true form is voiced by Kenichi Mochizuki (望月 健一, Mochizuki Ken'ichi).
- Statistics:
- Height: 228cm
- Weight: 145kg
The Worms
The Worms (ワーム, Wāmu) are an alien menace that blends into the human population by copying the faces of their victims along with their memories and personalities. While most are in pupa form known as a Salis, few Worms molt into an adult form with the ability to Clock Up. During the events of the first episode, a Culex Worm mimics Natsumi as it and its group, composed of the Geophilid Worm, Sectio Worm and Sepultura Worm, attempt to kill her until Tsukasa becomes Decade for the first time.
- Coleoptera Worm Argentum (コレプテラワーム・アージェンタム, Koreoputera Wāmu Ājentamu, 16): The first Worm Tsukasa encounters in Kabuto's world that it assumed the form of a young man. After the ZECT Troopers confine it, Gatack and TheBee attempt to fight the Worm who overwhelmed them in its Clock Up state. But with the unseen aid of Kabuto, the Worm is destroyed by TheBee.
- Geophilid Worm (ジオフィリドワーム, Jiofirido Wāmu, 16): A Worm that targeted Mayu, it is destroyed by Decade in Kuuga's Pegasus Form.
- Subst Worm (サブストワーム, Sabusuto Wāmu, 17): A Worm that posed as a young man and targeted Mayu, chasing her and Natsumi down until it was destroyed by a shockwave from Mayu's transformation into the Sisyra Worm.
Hibiki's World
Hibiki's World (響鬼の世界, Hibiki no Sekai) is the version of reality where Kamen Rider Hibiki takes place. In this world, though modern in appearance, the people are dressed in feudal Japanese attire with the Oni divided by three rival Ongekidō (音撃道, Ongekidō) style variations that have different views on the Grand Master (大師匠, Daishishō) who founded the style and wrote in down in three scrolls divided among the classes. The painting used to enter this world depicts a forest with a taiko drum in the foreground. It also should be noted that the majority of the original cast return to reprise their roles.
Hibiki
Hibiki (ヒビキ, Hibiki) has the ability to transform into Kamen Rider Hibiki (仮面ライダー響鬼, Kamen Raidā Hibiki) who is master of the drumming Ongekidō Hibiki Style (ヒビキ流, Hibiki Ryū). However, he seems lazy and uninterested in being an Oni. He later turns into Gyūki (牛鬼, literally "Ox Demon"), an Oni-like legendary Makamou.
Hibiki is portrayed by David Ito (デビット 伊東, Debitto Itō), while his Gyūki form is voiced by Keikō Sakai (酒井 敬幸, Sakai Keikō).
- Gyūki's Statistics:
- Height: 270cm
- Weight: 350kg
Asumu
Asumu (アスム, Asumu) is Hibiki's child apprentice, able to assume a silvery Oni form called Asumu Transformed Form (アスム変身体, Asumu Henshin Tai). Though Hibiki no longer wants to teach him, Asumu still wants to become a full-fledged Oni just like his master Hibiki.
Asumu is portrayed by Kazuki Koshimizu (小清水 一揮, Koshimizu Kazuki).
Ibuki
Ibuki (イブキ, Ibuki) has the ability to transform into Kamen Rider Ibuki (仮面ライダー威吹鬼, Kamen Raidā Ibuki) who is master of the trumpet-blowing Ongekidō Ibuki Style (イブキ流, Ibuki Ryū), running the Ibuki Lesson Studio. He later joins the fight without his "mask" against the Bakegani wielding a trombone version of the Ongekidan Reppu.
Jouji Shibue (渋江 譲二, Shibue Jōji) reprises his role as Ibuki.
Akira
Akira (アキラ, Akira) is Ibuki's head apprentice who has the ability to transform into Kamen Rider Amaki (仮面ライダー天鬼, Kamen Raidā Amaki) whose visually resembles Ibuki.
Nana Akiyama (秋山 奈々, Akiyama Nana) reprises her role as Akira.
Zanki
Zanki (ザンキ, Zanki) has the ability to transform into Kamen Rider Zanki (仮面ライダー斬鬼, Kamen Raidā Zanki) who is master of the guitar-playing Ongekidō Zanki Style (ザンキ流, Zanki Ryū), stationed at a dojo. He is Ibuki's rival and thus their schools are sworn enemies. He later joins the fight without his "mask" against the Bakegani wielding his OngekiShingen Retsuzan.
Kenji Matsuda (松田 賢二, Matsuda Kenji) reprises his role as Zanki.
Todoroki
Todoroki (トドロキ, Todoroki) is Zanki's head apprentice who has the ability to transform into Kamen Rider Todoroki (仮面ライダー轟鬼, Kamen Raidā Todoroki). Though a member of Zanki's school, he has feelings for Akira.
Shingo Kawaguchi (川口 真五, Kawaguchi Shingo) reprises his role as Todoroki.
Makamou
The Makamou (魔化魍, Makamō) are an assortment of monstrous creatures that usually dwell in the rural areas of Japan and consume any human beings as food. There are two main variations of this group, the bestial Giant Type and the humanoid Summer Type. In the first episode, Makamou such as the Bakegani and Ooari attack Natsumi while others like the Ubume were involved in the all-out battle among the monster groups that destroys the world.
- Kappa (カッパ（河童）, 18): A Summer Type Makamou, it was first one that Tsukasa and company encounter before Asumu arrives to fight it. In the end, the Kappa is killed by Decade using Kabuto's power on it.
- Bakeneko (バケネコ（化猫）, 18): A trio of Summer Type Makamou, while the first two were killed by Zanki and Ibuki, the last one evaded them before being killed by Decade.
- Tengu (テング（天狗）, 18): A Summer Type Makamou that attacked Hibiki and Asumu, overpowering Kuuga until Hibiki assumes his Oni form and kills the Makamou.
- Bakegani (バケガニ（化け蟹）, 19): A Giant Type Makamou.
Nega World
Nega World (ネガの世界, Nega no Sekai) is a parallel world much like the one Natsumi and Tsukasa come from, home to the evil Kamen Riders. The painting used to enter this world depicts the destruction of the first world caused by the monsters' conflict among themselves.
Otoya Kurenai
Otoya Kurenai (紅 音也, Kurenai Otoya) is a young man who leads the Riders of his world. Through Kivat the 2nd, Otoya transforms into Kamen Rider Dark Kiva (仮面ライダーダークキバ, Kamen Raidā Dāku Kiba).
Kouhei Takeda (武田 航平, Takeda Kōhei) reprises his role as Otoya Kurenai.
Other Kamen Riders
- Alternative (オルタナティブ, Orutanatibu): Under Otoya.
- Kamen Rider Ryuga (仮面ライダーリュウガ, Kamen Raidā Ryūga):
- Kamen Rider Orga (仮面ライダーオーガ, Kamen Raidā Ōga):
- Kamen Rider Dark Kabuto (仮面ライダーダークカブト, Kamen Raidā Dāku Kabuto):
Cameo appearances
Various characters in Kamen Rider Decade are directly from their original Heisei Rider Series and are portrayed by the original actors. These characters do not appear to be affiliated with any side, as some assist Tsukasa, while others seek to fight Decade.
Wataru Kurenai
A mysterious young man, Wataru Kurenai (紅 渡, Kurenai Wataru) is the one to tell Tsukasa about the nine universes merging into one and froze the world in place with the aid of his allies to give Tsukasa time to stop its destruction. In Kamen Rider Kiva, Wataru is the one who could transform into the title Rider, Kamen Rider Kiva (仮面ライダーキバ, Kamen Raidā Kiba).
Koji Seto (瀬戸 康史, Seto Kōji) reprises his role as Wataru Kurenai.
Sou Yaguruma
Sou Yaguruma (矢車 想, Yaguruma Sō) is a young man in Kamen Rider Kabuto who transformed into Kamen Rider Kick Hopper (仮面ライダーキックホッパー, Kamen Raidā Kikku Hoppā). In Decade, Kick Hopper is a wild card Kamen Rider who uses a fighting style themed around kicking attacks. He and his partner Punch Hopper appear in Kuuga's World during a dimensional distortion caused by Narutaki to fight Decade. However, when they start focusing their rage on Kuuga, Narutaki causes another dimensional distortion that sends the two to another world.
Hidenori Tokuyama (徳山 秀典, Tokuyama Hidenori) reprises his role as Sou Yaguruma, voicing Kick Hopper.
Shun Kageyama
Shun Kageyama (影山 瞬, Kageyama Shun) is a young man in Kamen Rider Kabuto who transformed into Kamen Rider Punch Hopper (仮面ライダーパンチホッパー, Kamen Raidā Panchi Hoppā). In Decade, Punch Hopper is a wildcard Kamen Rider who uses a fighting style themed around punching attacks.
Masato Uchiyama (内山 眞人, Uchiyama Masato) reprises his role as Shun Kageyama, voicing Punch Hopper.
Masato Kusaka
Masato Kusaka (草加 雅人, Kusaka Masato) is a young man in Kamen Rider 555 who transformed into Kamen Rider Kaixa (仮面ライダーカイザ, Kamen Raidā Kaiza). In Decade, Kaixa is a wildcard Kamen Rider who attacks Decade after he is taken to another world by Kivala. He is under the impression that Decade is a hinderance to his own agenda and seeks to take the Decadriver from him. He eventually concedes when Decade is returned to Kiva's World.
Kohei Murakami (村上 幸平, Murakami Kōhei) reprises his role as Masato Kusaka, voicing Kaixa.
Takeshi Asakura
Takeshi Asakura (浅倉 威, Asakura Takeshi) is a young man in Kamen Rider Ryuki who transformed into Kamen Rider Ohja (仮面ライダー王蛇, Kamen Raidā Ōja). In Decade, Ohja appears in Hibiki's World wielding a kanabō which he uses to summon a Bakegani that attacks the other Riders.
Takashi Hagino (萩野 崇, Hagino Takashi) reprises his role as Takeshi Asakura, voicing Ohja.