|This article is about a/an episode in Kamen Rider Den-O.|
Change Imagin World (チェンジ・イマジン・ワールド Chenji Imajin Wārudo) is the fortieth episode of Kamen Rider Den-O. It is the debut of Zeronos Zero Form.
With the people of the world altered from Yuto's removal from time, Ryotaro tries to figure out how to bring him back while dealing with Kai's manipulations.
Succeeding in his machinations, Kai erases Yuto from the future timeline, causing the Milk Dipper to become a girls' hang out with Yuto gone as well. Furthermore, as only Kohana and the Owner remember Yuto, too, Deneb is now contracted to Ryotaro and part of the DenLiner crew. Later, while Ryotaro and Kohana ponder the Owner's words about memory's effects on people and the nature of Singularity Points, the girl gets taken by the male Snail Imagin. Ax Form attempts to fight until Kai reveals himself with the Gecko and Newt Imagin as backup. Kai reveals to Ryotaro that Sakurai is the true target of the Imagin, with his removal from existence allowing the future Kai came from to be realized. Though Ryotaro understood that Yuto's absence had a positive effect on the present, he could not accept it if it meant that Yuto sacrificed himself in vain. Meeting Kai again, Ryotaro tells him that he figured the future is not truly decided, causing everything to return to normal. Annoyed, Kai summons his Imagin to kill Ryotaro and Kohana. But Yuto arrived at the last second, having created new memories in the present through his actions as Zeronos. Seeing no chance, Kai sent the male Snail Imagin back into time while having the other two Imagin remain to fight. While Zeronos goes back in time after the Snail Imagin, Den-O deals with the two Imagin before assuming Climax Form to defeat them. At February 1, 1999, the Snail Imagin attempts to kill Sakurai when Zeronos arrives to fight. At the last second, Zeronos uses the unusual card with a red Z that he received from his future self to assume Zero Form. Though he destroyed the Snail Imagin, Yuto loses a portion of his own memories related to Airi, who also forgot about meeting the younger Yuto as well.
- Den-O: Axe Form, Plat Form, Climax Form
- Zeronos: Altair Form, Zero Form
- Ryotaro Nogami (野上 良太郎 Nogami Ryōtarō): Takeru Satoh (佐藤 健 Satō Takeru)
- Kohana (コハナ Kohana): Tamaki Matsumoto (松元 環季 Matsumoto Tamaki)
- Yuto Sakurai (桜井 侑斗 Sakurai Yūto): Yuichi Nakamura (中村 優一 Nakamura Yūichi)
- Naomi (ナオミ Naomi): Rina Akiyama (秋山 莉奈 Akiyama Rina)
- Airi Nogami (野上 愛理 Nogami Airi): Wakana Matsumoto (松本 若菜 Matsumoto Wakana)
- Seigi Ozaki (尾崎 正義 Ozaki Seigi): Akira Nagata (永田 彬 Nagata Akira)
- Issē Miura (三浦 イッセー Miura Issē): Ryo Ueno (上野 亮 Ueno Ryō)
- Kai (カイ Kai): Hideo Ishiguro (石黒 英雄 Ishiguro Hideo)
- Momotaros (モモタロス Momotarosu, Voice): Toshihiko Seki (関 俊彦 Seki Toshihiko)
- Urataros (ウラタロス Uratarosu, Voice): Kōji Yusa (遊佐 浩二 Yusa Kōji)
- Kintaros (キンタロス Kintarosu, Voice): Masaki Terasoma (てらそま まさき Terasoma Masaki)
- Ryutaros (リュウタロス Ryūtarosu, Voice): Kenichi Suzumura (鈴村 健一 Suzumura Ken'ichi)
- Deneb (デネブ Denebu, Voice): Hōchū Ōtsuka (大塚 芳忠 Ōtsuka Hōchū)
- Owner/Opening Narration (オーナー／オープニングナレーション Ōnā/Ōpuningu Narēshon): Kenjirō Ishimaru (石丸 謙二郎 Ishimaru Kenjirō)
- Fortune Teller: Yuka Kyomoto (京本 有加 Kyōmoto Yuka)
- Snail Imagin (スネールイマジン Sunēru Imajin, Voice): Takashi Irie (入江 崇史 Irie Takashi)
- Newt Imagin (ニュートイマジン Nyūto Imajin): Kōji Yusa (遊佐 浩二 Yusa Kōji)
- Gecko Imagin (ゲッコーイマジン Gekkō Imajin): Kenichi Suzumura (鈴村 健一 Suzumura Ken'ichi)
- Kamen Rider Den-O/Momotaros: Seiji Takaiwa (高岩 成二 Takaiwa Seiji)
- Urataros: Eitoku (永徳 Eitoku)
- Kintaros: Jirō Okamoto (岡元 次郎 Okamoto Jirō)
- Ryutaros: Toshihiro Ogura (おぐら としひろ Ogura Toshihiro)
- Kamen Rider Zeronos: Makoto Ito (伊藤 慎 Itō Makoto)
- Deneb: Yoshifumi Oshikawa (押川 善文 Oshikawa Yoshifumi)
- Snail Imagin: Norihito Itō (伊藤 教人 Itō Norihito)
- Newt Imagin: Hiroaki Nakamura (中村 博亮 Nakamura Hiroaki)
- Gecko Imagin: Hidenaga Saito (斉藤 英長 Saitō Hidenaga)
- As part of Super Hero Time, this episode aired alongside Juken Sentai Gekiranger episode 37, Lesson 37: Gyan-Gyan! Useless Arranged Marriage Discussion.
- Viewership: 5.0%
- First appearance of Kamen Rider Zeronos' Zero Form and Denebick Buster
- This is the first time the opening song is changed to Climax Jump DenLiner Form
Blu-ray Box 3 comes with 13 episodes.