Kamen Rider Decade Episodes

{|width="98%" class="wikitable" !width="30"| # !Title !Writer !Original airdate
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"Raidā Taisen"
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 * id="ep1"|1
 * style="text-align: left;"|"Rider War"
 * Shō Aikawa
 * January 25, 2009
 * colspan="4" style="border-bottom: 3px solid rgb(204, 204, 255);"|After Natsumi Hikari has a nightmare of every Kamen Rider being defeated by a figure called Decade, she helps her grandfather Eijiro deal with unsatisfied customers. The photographer, Tsukasa Kadoya, seems to be at fault, but he simply tells Natsumi the photos are bad because he does not belong in this world. After the argument, various holes in reality open, allowing the Orphnoch, Undead, Makamou, Worms, Imagin, and Fangires to start terrorizing their world. In the bedlam, she finds a corroded belt and book, recalling it as Decade's from her dream. She gives Tsukasa the belt and book, allowing him to transform into Kamen Rider Decade by using a card from the book and inserting it into the belt. Using other cards, he fights the various monsters that have invaded his reality by transforming into Kamen Riders Kabuto, Faiz, and Hibiki. Back in his own reality, Tsukasa is warned by Wataru Kurenai that his reality is being superseded by the nine previous Kamen Riders' realities. He must go to their worlds and defeat the other Kamen Riders to save his own world, while Wataru keeps it frozen in place. Back in the Hikari Studio, Eijiro reveals a large photo that shows another world. Stepping outside, Tsukasa finds himself in this world as a police officer while Kamen Rider Kuuga appears to aid the police against two Grongi.
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The World of Kuuga
"Kūga no Sekai"
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 * id="ep2"|2
 * style="text-align: left;"|"The World of Kuuga"
 * Shō Aikawa
 * February 1, 2009
 * colspan="4" style="border-bottom: 3px solid rgb(204, 204, 255);"|Arriving in the World of Kuuga, Tsukasa takes the guise of a policeman and watches Kuuga destroy a pair of Grongi, Ra-Dorudo-Gu and Me-Gyarido-Gi, before reverting to his human form, Yuusuke Onodera. Tsukasa later kills Go-Baberu-Da as Decade, but is mistaken for a Grongi by Yuusuke and Ai. When Yuusuke and Ai arrive at the Hikari Studio to discuss this strange Grongi, Tsukasa offers Ai his help in solving the mystery behind the Grongi's female targets and the location of their lair. On the foot of Mount Hitoki, the Grongi's Lair, Tsukasa reveals he used Ai as bait to lure out the remaining Grongi, revealing their plan to revive their leader before ruining their game. While attempting to destroy the Grongi, Decade is attacked by Kuuga, who reveals he knows about Decade's mission and will stop him at all costs. Natsumi pleads for them to stop, recalling her dream in which Decade and Kuuga seemingly destroy each other. A dimensional rift occurs, and their fight is interrupted by the appearance of Kamen Riders Kick Hopper and Punch Hopper.
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Transcendence
"Chōzetsu"
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 * id="ep3"|3
 * style="text-align: left;"|"Transcendence"
 * Shō Aikawa
 * February 8, 2009
 * colspan="4" style="border-bottom: 3px solid rgb(204, 204, 255);"|After fending off the Hoppers who disappeared into another dimensional rift, Yuusuke reveals he was told of Decade by a mysterious man. When Ai and her task force go to investigate Mount Hitoki, a black mist begins to rise from within, signaling the revival of N-Gamio-Zeda. Resurrected by the dimensional chaos, he uses his miasma to convert humans into Grongi. While Yuusuke saves Ai and takes her to the hospital, Tsukasa fights the Grongi alone. A dying Ai requests Yuusuke to overcome his angst and fight to protect everyone's smiles, and so Kuuga and Decade work together to destroy the remaining Grongi. N-Gamio-Zeda, in a last effort, absorbs all the Grongi to power himself up, but he is ultimately overpowered by both Decade and Kuuga, who destroy him with a combo attack. After returning to the hospital, Yuusuke finds that Ai has died and vows to honor her dying wish, setting off on his own journey with a mysterious white bat following him. Meanwhile, Tsukasa and Natsumi return to the photo studio, preparing to leave for the next world in their journey.
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Second Movement ♬ Prince Kiva
"Dai Ni Gakushō ♬ Kiba no Ōji"
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 * id="ep4"|4
 * style="text-align: left;"|"Second Movement ♬ Prince Kiva"
 * Shō Aikawa
 * February 15, 2009
 * colspan="4" style="border-bottom: 3px solid rgb(204, 204, 255);"|Arriving in the World of Kiva, Tsukasa and company discover that the Fangires of this world have made a truce with the humans. However, when Tsukasa finds the Lion Fangire attacking a young woman, he transforms into Decade to fight him. Wataru, the King of the Fangire Race, witnesses this and becomes Kamen Rider Kiva to fight him with the aid of his Arms Monsters, forcing Decade to assume Kamen Rider Kuuga's Mighty, Titan, and Dragon Forms to counter. Yuusuke manages to stop the fight, and the Swallowtail Fangire reveals that the young woman was actually a renegade Fangire. Yuusuke reveals he has promised to help Wataru because he is uncomfortable with being the King. After meeting a mysterious man who is disgusted with the human/Fangire treaty, Tsukasa later encounters Kivala, who uses her power to send him into another world where he is attacked by Kamen Rider Kaixa. Back in the World of Kiva, after having fed on many humans, the Beetle Fangire arrives at Castle Doran with the intent to kill Wataru and take his place as the King.
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The Biting King's Qualifications
"Kamitsuki Ō no Shikaku"
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 * id="ep5"|5
 * style="text-align: left;"|"The Biting King's Qualifications"
 * Shō Aikawa
 * February 22, 2009
 * colspan="4" style="border-bottom: 3px solid rgb(204, 204, 255);"|As Tsukasa is fighting against Kaixa in another dimension, the Beetle Fangire defeats Wataru and becomes the new Fangire king, claiming Kivat. After the new King dissolves the truce, Yuusuke arrives to protect Wataru before the boy runs off. After Yuusuke expresses his reasons for helping the dethroned boy, Wataru takes refuge in the Hikari Studio. After being caught up on current events, Tsukasa makes his way to Castle Doran to save Yuusuke as the Beetle Fangire absorbs the Arms Monsters into himself. After killing the Swallowtail Fangire, Decade encounters the Beetle Fangire, who assumes Kiva's DoGaBaKi Form. When their fight makes its way to Yuusuke and Wataru, the boy finds his courage to overcome his Fangire impulses and declares himself the King once more. He takes back the Kiva power and helps Decade battle the Beetle Fangire, mortally wounding him with a Darkness Moon Break/Dimension Kick combo. Later, Tsukasa pays a final visit to the Kurenai manor to play a final song for the dying Beetle Fangire, whom he knew was the man he met earlier and is Wataru's father. Soon after, as Yuusuke moves into the Hikari Studio with Kivala sneaking in, the group prepares to enter yet another world.
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Battle Trial: Ryuki World
"Batoru Saiban: Ryūki Wārudo"
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 * id="ep6"|6
 * style="text-align: left;"|"Battle Trial: Ryuki World"
 * Shō Aikawa
 * March 1, 2009
 * colspan="4" style="border-bottom: 3px solid rgb(204, 204, 255);"|Upon arriving in the World of Ryuki, Natsumi goes to the Atashi Journal headquarters to learn about the world's Kamen Riders from its editor, Reiko Momoi. After Natsumi's arrival at the journal's offices, Reiko is mysteriously killed, leaving Natsumi as the culprit as she had a small fork in her hand. Natsumi is arrested under suspicion of murder, and is to be sentenced with a Kamen Rider Trial: a system where Kamen Riders fight in the Mirror World to determine the outcome of criminal cases. Natsumi calls upon Tsukasa to be her lawyer, who meets with Shinji Tatsumi to hear what he knows of what happened to Reiko. As Shinji reveals that he is Kamen Rider Ryuki and he believes Natsumi was framed, his former friend Kamen Rider Knight is fighting in the Kamen Rider Trial, defeating several opponents. Shinji suggests to Tsukasa that he should fight as Decade in the Kamen Rider Trial to clear Natsumi's name. At the scene, he finds that Ren Haguro was also at the scene of the crime before he is brought into the Mirror World along with the sub-editor of the Atashi Journal: Kamata. Decade and Abyss' fight, however, is interrupted by Kamen Rider Imperer, and Abyss leaves to watch Decade's abilities. Elsewhere, Shinji confronts Ren, believing he is Reiko's real killer, and he challenges him as Kamen Rider Ryuki. Their fight is also interrupted by Decade, having just defeated Imperer and now turning his sights on Knight, easily overwhelming him in Kiva's various forms with Shinji watching.
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Super Trick of the Real Criminal
"Chō Torikku no Shinhannin"
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 * id="ep7"|7
 * style="text-align: left;"|"Super Trick of the Real Criminal"
 * Shō Aikawa
 * March 8, 2009
 * colspan="4" style="border-bottom: 3px solid rgb(204, 204, 255);"|After defeating Knight, Decade is about to finish him off when Ryuki pleads with him not to deliver the final blow, as he feels Knight must answer for his crime by his hand. However, Abyss uses this time to make his move to take out all three Riders at once, forcing them to retreat with Ren refusing to answer Shinji as he leaves. After her brief encounter with Narutaki, Natsumi learns that Shinji and Tsukasa are convinced that Ren is Reiko's murderer, although Yuusuke sees otherwise. Meanwhile, a wounded Ren battles Kamen Rider Odin and defeats him, emerging from Mirror World with Odin's Time Vent as Shinji and Yuusuke find him. Learning that Ren obtained the card to save Reiko, Shinji uses the card to go back in time as Tsukasa holds Abyss off. Arriving seconds before Reiko's death, Shinji and Tsukasa manage to save Reiko with the latter cornering her true murderer, Kamata. Despite this, Kamata arrives and absorbs his past self before becoming Abyss and unleashing his monsters on Decade. After learning the truth behind Ren coming to the Atashi Journal and why he left, a relieved Shinji runs to Tsukasa's aid. Though the two manage to defeat Abyss together, they learn from Narutaki that Kamata is actually an Undead as the two depart. After he receives Shinji's photo of himself and Yuusuke, Tsukasa and company enter the World of Blade.
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Welcome to the Blade Restaurant
"Bureido Shokudō Irasshaimase"
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 * id="ep8"|8
 * style="text-align: left;"|"Welcome to the Blade Restaurant"
 * Shōji Yonemura
 * March 15, 2009
 * colspan="4" style="border-bottom: 3px solid rgb(204, 204, 255);"|Arriving in the World of Blade, Tsukasa assumes the disguise of the Chief Waiter of the BOARD Corporation, an organization whose agents become Kamen Riders to battle the Undead. When the Elephant Undead goes on the attack, Sakuya Hishigata battles the Undead as Kamen Rider Garren as Kazuma Kendate arrives and transforms into Kamen Rider Blade. When the Capricorn Undead joins the fray, Tsukasa joins the fight, dispatching the Elephant Undead using Ryuki's powers. Afterwards, Natsumi and Yuusuke meet BOARD's president Hajime Shijo, who decides to promote Tsukasa to the rank of King while Kazuma Kendate is demoted from Ace to 7. As a result, he is forced to work under Tsukasa in the cafeteria. When he is forced to give up the Blay Buckle after being demoted a second time, Kazuma refuses and runs off. Just as Tsukasa tries to convince Kazuma to do the right thing, Kamata arrives and attacks them as the Paradoxa Undead. As Decade battles the Paradoxa Undead with the Capricorn Undead backing him up, Kazuma becomes Blade and fights Garren and Leangle. However, both fights are interrupted with the appearance of Kamen Rider Chalice, who takes the Blay Buckle off of Kazuma and takes out the other Riders before fighting Decade one-on-one.
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Blade Blade
"Bureido Burēdo"
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 * id="ep9"|9
 * style="text-align: left;"|"Blade Blade"
 * Shōji Yonemura
 * March 22, 2009
 * colspan="4" style="border-bottom: 3px solid rgb(204, 204, 255);"|Decade continues his fight with Chalice, with Garren losing his Garren Buckle in the process. The fight comes to a sudden halt when Kamen Rider Todoroki shows up. Back at BOARD, Hishigata is demoted to Rank 3 while Kazuma is fired from BOARD. After he understands Tsukasa's intent to help him, Kazuma stays on in the kitchen as he opens the Ace Lunch to all BOARD members. Meanwhile, Mutsuki and Hishigata search for Chalice to get back the Rider systems, and are subsequently ambushed by Chalice, who knocks them out after they find out his true identity. After hearing that the two have supposedly resigned from the company, Kazuma decides to find Hajime with Yuusuke's help. As Tsukasa meets a mysterious figure who recognizes him, Kazuma and Yuusuke arrive too late to save Hishigata and Mutsuki as Hajime uses the created card from the Rider Systems to become the Joker, revealing his reasons to Kazuma. Decade arrives as Ryuki with the Blay Buckle and gives Kazuma the resolve to fight back. Once Kazuma becomes Blade, he and Decade destroy the two Undead together. Soon after parting ways with Kazuma, Tsukasa and company begin their next venture into the World of Faiz.
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Faiz High School's Phantom Thief
"Faizu Gakuen no Kaitō"
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 * id="ep10"|10
 * style="text-align: left;"|"Faiz High School's Phantom Thief"
 * Shō Aikawa
 * March 29, 2009
 * colspan="4" style="border-bottom: 3px solid rgb(204, 204, 255);"|Upon arriving in the World of Faiz and once more encountering the mysterious Daiki Kaito, Tsukasa finds himself in a school uniform and enrolled at Smart Brain High School. He learns that the high school is attacked on a nightly basis by beings called the Orphnoch, with only Faiz to protect the school. Daiki challenges Tsukasa to find out who Faiz is, and Tsukasa then challenges the Lucky Clover clique to a tennis match to see if any of them are Faiz. He beats them, learning that they are Orphnoch who are also after Faiz, and is forced to become Decade, using Blade's power against them. However, Decade is outclassed when Momose appears as the Tiger Orphnoch and warns him to back off. Daiki then confronts the group, giving them a hint as to who Faiz is before going off. Then, the Lucky Clover members target Yuri Tonoda and Takumi Ogami, believing Yuri is Faiz until Takumi transforms and fights them off. When Tsukasa learns that Yuri is the target, he goes off to fight the Orphnoch, watching Faiz get defeated and losing the belt. The fight is then interrupted by Daiki Kaito who transforms into Kamen Rider Diend while revealing he used the Lucky Clover to take the belt for himself. Once the Centipede Orphnoch is destroyed, Decade and Diend have a stand off over the Faiz Belt as Momose attacks Yuri as the Tiger Orphnoch only to meet his match with Takumi who transforms into the Wolf Orphnoch to protect his friend.
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555 Faces, 1 Treasure
"Faizutsu no Kao, Hitotsu no Takara"
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 * id="ep11"|11
 * style="text-align: left;"|"555 Faces, 1 Treasure"
 * Shō Aikawa
 * April 5, 2009
 * colspan="4" style="border-bottom: 3px solid rgb(204, 204, 255);"|After Tsukasa recovers the Faiz Gear, he learns Diend's reasons for wanting the belt before Takumi regains it so he and a shocked Yuri can escape on the Autovajin. However, as he exposed himself as the Wolf Orphnoch to protect her only to be forsaken, a saddened Takumi attempts to dispose of the Faiz Gear into the river. Managing to save the Gear while following him, Tsukasa returns to the photo studio where he put Yuri's confusion at ease. The next day, Daiki attacks Takumi to get the belt from him, nearly killing him when Tsukasa arrives with it. Refusing to take Tsukasa's words of something more precious than the Faiz Gear seriously, Daiki takes Decade's Ride Booker, and Narutaki takes advantage of the situation as he takes Tsukasa into another dimension to be killed by Kamen Rider Ryuga. However, after interrogating Kivala on the whereabouts, Daiki intervenes while claiming it was to get the Faiz Gear as he gives Tsukasa back the Ride Booker. While this occurs, the remaining Lucky Clover members start taking over the school to sire more of their kind until Takumi arrives to fight them in Orphnoch form. Though no match, Takumi attempts to protect Yuri's camera until Tsukasa arrives as he regains Faiz's Ride Cards. Decade and the Wolf Orphnoch are outmatched until Daiki arrives with the Faiz Gear and gives it to Takumi. The two transform and kill the Dragon and Lobster Orphnoch. However, the Tiger Orphnoch revives his followers, and Decade counters with the Final AttackRide Faiz Blaster, killing him and his followers in one shot. As Takumi and Yuri rekindle their friendship, Daiki steals the Orga Belt from the ruins of the school, and Tsukasa follows him to the World of Agito.
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Reunion: Project Agito
"Saikai: Purojekuto Agito"
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 * id="ep12"|12
 * style="text-align: left;"|"Reunion: Project Agito"
 * Shō Aikawa
 * April 12, 2009
 * colspan="4" style="border-bottom: 3px solid rgb(204, 204, 255);"|Upon arriving in the World of Agito, Yuusuke is shocked that there are Grongi in the world which are being dealt with by Kamen Rider G3-X. He is further shocked when he sees an interview with Toko Yashiro, who is physically identical to the Ai Yashiro that died back in the World of Kuuga. Arriving at the police station, Yuusuke offers to be the new user of the G3-X suit, but loses the position to Kaito. While this occurs, finding himself in a mailman outfit with a letter to Shouichi Ashikawa, Tsukasa and Natsumi find the man before they are attacked by what they think to be a Grongi. But during the fight, Tsukasa realizes he is fighting an Unknown, an Ant Lord called Formica Pedes. After killing the Pedes, Shouichi refuses the letter before he and Tsukasa dodge an attack meant for him by a mysterious Unknown. Later that night, as Tsukasa reads the letter's contents, Yuusuke leaves the Hikari Studio to remain in the World of Agito with Toko. The next day, Kaito is deployed as G3-X to take out the Grongi with Yuusuke supporting him. During the fight, Kaito takes off the armor to finish the Grongi off as Diend, revealing that he only became G3-X for his own agenda. Though he kills Me-Ginoga-De, Zu-Mebio-Da attempts to run off only to killed by a couple of Formica Pedes. While this occurs, Tsukasa finds Shouichi and offers protection, only to see him transform into Exceed Gills. Tsukasa attempts to restrain him as Kiva in Garulu Form. Gills, in pain of sensing the Pedes' attack, runs off and kills them both before Yuusuke's eyes. When Diend targets Gills, Decade tries to protect him, only to have his belt stolen by Gills with no defense against Diend's summoned Delta's Lucifer's Hammer finisher.
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Awakening: Tornado of Souls
"Kakusei: Tamashii no Torunēdo"
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 * id="ep13"|13
 * style="text-align: left;"|"Awakening: Tornado of Souls"
 * Shō Aikawa
 * April 19, 2009
 * colspan="4" style="border-bottom: 3px solid rgb(204, 204, 255);"|After Yuusuke saves Tsukasa from Delta's attack, Gills is about to fight when he's overcome with pain as the Unknown shows up to kill him. As Shouichi escapes, Toko recognizes him via G3-X's camera. While Tsukasa insists on protecting an annoyed Shouichi, Yuusuke reports the defeat of the Grongi and the emergence of the Unknown. He finds finds Toko saddened, but has little time to help her as Kaito takes the G4 chip stored within his locker. Yuusuke demands the chip back, but during the struggle, Toko blasts the chip to bits and a dissappointed Kaito leaves. The next day, as Tsukasa continues to keep Shouichi safe from the Unknowns' attack, Yuusuke learns that Shoichi was the original user of the G3 suit when he receives the letter for Shouichi from Toko. As Gills fights the Buffalo Lord Taurus Ballista, Yuusuke arrives in the G3-X suit to make Shouichi realize that Toko knew the truth and it was the reason for creating the G3-X suit. Diend arrives to selflishly aid them with Blade's power until Ballista arrives. But Tsukasa shows up to state the Buffalo Lord's idealogic flaws as Shouichi awakens as Agito. As Diend takes his leave, Decade, Agito, and G3-X battle Ballista and Formica Regia before the latter is killed by Agito. After turning Agito into the Agito Tornador, Decade and G3-X ride on the hoverboard to finish the Lord off. Soon after, Yuusuke gives Toko his thanks as he says goodbye to her, and Shouichi returns to resume his place by Toko's side as Agito. As Kivala is happy to see Yuusuke returning to the Studio, the gang ends up in another world: the World of Den-O.
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Cho Den-O Beginning
"Chō Den'ō Biginingu"
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 * id="ep14"|14
 * style="text-align: left;"|"Cho Den-O Beginning"
 * Yasuko Kobayashi
 * April 26, 2009
 * colspan="4" style="border-bottom: 3px solid rgb(204, 204, 255);"|When the Hikari Studio appears in the World of Den-O, Tsukasa finds himself dressed in a strange detective-like attire with possession of a Rider Pass. He is then suddenly possessed by an Imagin, who battles a Mole Imagin as Kamen Rider Den-O. After taking out the Imagin, the possessed Tsukasa walks off until Natsumi uses her pressure point move to drive the Imagin out of him. When the Imagin known as Momotaros tries to possess Tsukasa, again, he throws Yuusuke in front of him and Yuusuke becomes possessed. After easily overcoming M-Yuusuke and treating him to pudding for answers, Tsukasa learns that the Imagin lost his physical form some time before they arrived. The possessed Yuusuke then runs out of the Hikari Studio to go after the other Mole Imagin with Tsukasa and Natsumi close behind as they look for the DenLiner to solve the mystery. However, Urataros, Kintaros, and Ryutaros possess Tsukasa and chase after Natsumi for answers. When Tsukasa forces the three out and they enter Natsumi to fight him, Decade uses Agito's power on each form while a mysterious Kamen Rider and his lackies attack a group of delivery men, with the Alligator Imagin taking adventage of the chaos. When a dimensional rift sends Decade and Den-O into the dimension where Natsumi saw the Rider War, the two Kamen Riders reach a stalemate as they are picked up by the DenLiner. While the DenLiner's Owner realizes that they have to work together, Yuusuke and Momotaros as Den-O are in a losing battle against Diend with as Narutaki witness.
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Here Comes Cho Momotaros!
"Chō Momotarosu, Sanjō!"
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 * id="ep15"|15
 * style="text-align: left;"|"Here Comes Cho Momotaros!"
 * Yasuko Kobayashi
 * May 3, 2009
 * colspan="4" style="border-bottom: 3px solid rgb(204, 204, 255);"|After getting on the DenLiner, Tsukasa takes pictures of the DenLiner's gang before the Taros. But after Kohana sets the three Imagin in their place, they suddently find the Hikari Studio as the front car. Kohana explains to Natsumi about the Imagin's new attack pattern as well as Momotaros, who Tsukasa decides to find. After surviving his confrontation with Diend and taking out another Mole Imagin, M-Yuusuke tends to his injuries as Tsukasa finds him and scolds him for being a idiot. M-Yuusuke senses the Imagin boss, and he and Tsukasa chase after the Alligator Imagin until he reveals himself. Using the Mole Imagin to cover his escape into the past, the Alligator Imagin battles Den-O and Decade, using the former's own DenGasher against him. After Decade saves Den-O's life and attempt, Diend makes his presence known with his Riotroopers holding the Alligator Imagin at bay as he once more offers Momotaros a physical form as a DenLiner. But Decade takes the card, poorly defending Momotaros and giving him back his sense of self as he regains access to Den-O's powers. As the Alligator Imagin destroys the Riotroopers, Decade uses the modified Den-O Final Form card to give Momotaros back his original physical form. After a misunderstanding from Yuusuke, Decade gives Momotaros the power to execute his Decade Version Extreme Slash with Kuuga Gouram. As Momotaros returns to the DenLiner, only to receive a violent welcome back from the gang, Tsukasa and company were about to enter the World of Kabuto when they get a unexpected visit from the Imagin Sieg. With a manuscript on Sieg's person, it appears that the adventures in the World of Den-O are far from over.
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Warning: Kabuto Running Amok
"Keikoku: Kabuto Bōsōchū"
 * -style="background: rgb(242, 242, 242) none repeat scroll 0% 0%; text-align: center; -moz-background-clip: -moz-initial; -moz-background-origin: -moz-initial; -moz-background-inline-policy: -moz-initial;"
 * id="ep16"|16
 * style="text-align: left;"|"Warning: Kabuto Running Amok"
 * Kenji Konuta
 * May 10, 2009
 * colspan="4" style="border-bottom: 3px solid rgb(204, 204, 255);"|After helping the DenLiner gang in the past, Tsukasa and company begin their venture in the World of Kabuto. Posing as a ZECT Trooper, Tsukasa is deployed to aid Bright Troopers in the containment of a Worm as Kamen Riders Gatack and TheBee manage to exterminate it with the unseen aid of Kabuto. Soon after, Tsukasa brings Arata to the Studio to explain about his world, only to find a Worm had mimicked Tsukasa's form. After Natsumi uses the pressure point to expose one of the Tsukasas as a Worm, Decade fights it before it attacks a girl and is destroyed by Kabuto. Deciding to investigate the girl Mayu, they host a photo shoot for her, and Natsumi learns of Mayu's older brother who was supposedly killed by Kabuto. At ZECT's headquarters, TheBee's user, Sou Otogiri, tells Arata that the final prepation for the plans to capture Kabuto are nearly done. Tsukasa talks with Mayu more about her brother after attempting to help at her grandmother's oden shop, the Heaven House, and when walking back to the Hikari Studio they are attacked by a Geophilid Worm. Tsukasa destroys it as Kuuga Pegasus Form, and is then attacked by TheBee and Gatack. After being unable to use Den-O's powers against the Riders, Decade is eventually assisted by Diend who fights Gatack to gain his Clock Up system while TheBee and Decade battle, eventually becoming Faiz in Axel Form to match TheBee's Clock Up. When Decade realizes Mayu is in the same area being attacked by Worms, he goes off to save her but is intercepted by an attack from TheBee. Just as TheBee's stray shots are within inches of Mayu, Kabuto arrives to save her from both the attack and the Worms, disappearing as everyone's transformations end. However, when Mayu sees Sou, she recognizes him as her brother.
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The Grandma Way of Taste
"Obaachan Aji no Michi"
 * -style="background: rgb(242, 242, 242) none repeat scroll 0% 0%; text-align: center; -moz-background-clip: -moz-initial; -moz-background-origin: -moz-initial; -moz-background-inline-policy: -moz-initial;"
 * id="ep17"|17
 * style="text-align: left;"|"The Grandma Way of Taste"
 * Kenji Konuta
 * May 17, 2009
 * colspan="4" style="border-bottom: 3px solid rgb(204, 204, 255);"|Believing that TheBee's user is her brother, Mayu attempts to look for him with Natsumi's aid until they are attacked by a Worm. Counting on Kabuto to save them, Diend fights him to acquire his Clock Up system, summoning Ixa and Psyga to hold him down before Kabuto defeats them and runs off. By the time Tsukasa finds Natsumi and Mayu, the latter is shocked that she became a Worm as she runs off. She runs into Sou who reveals himself as the Phylloxera Worm and brings her to ZECT HQ as part of the Kabuto Capture plan, much to Arata's dismay before he is beaten to a bloody pulp questioning the plan. After escaping, Arata makes his way to Tsukasa and reveals the plan to him, confirming Tsukasa's notion. Kabuto falls for the trap as the Clock Down takes effect while the Worms reveal themselves among the ZECTroopers, with Sou exposing Kabuto as Mayu's real brother Souji. Tsukasa arrives and reveals the truth behind the Phylloxera Worm to Mayu while explaining that Souji and Mayu are still family regardless of the latter being a Worm. But believing he has the advantage, the Phylloxera Worm sics his Worm minions on Tsukasa. Souji frees Mayu and joins Tsukasa as they assume their Rider forms to finish off the Salis Worms before forcing the Phylloxera Worm into the open. Decade and Kabuto finish him off, but the tower projecting the Clock Down waves is destroyed in the process, forcing Souji to fade back into Clock Up space with Mayu watching. After taking Mayu home and giving Daiki a "treasure" for his trouble, Tsukasa and company begin the final phase of their journey. But as they deal with two Kivalas fighting over which of them is fake, the real Kivala is with Narutaki as he decides to personally deal with Decade in the final world, the World of Hibiki.
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Idle Hibiki
"Saboru Hibiki"
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 * id="ep18"|18
 * style="text-align: left;"|"Idle Hibiki"
 * Shōji Yonemura
 * May 24, 2009
 * colspan="4" style="border-bottom: 3px solid rgb(204, 204, 255);"|Arriving in the last world, the World of Hibiki, Tsukasa and company begin the search for Kamen Rider Hibiki when they are ambushed by the Makamou Kappa. An Oni in training named Asumu battles the monster until Decade uses Kabuto's powers to kill it. On learning he is Hibiki's pupil, Tsukasa has Asumu bring him to his mentor. Upon seeing Tsukasa, Hibiki, who is shirking off from his duties as an Oni, believes him to be the legendary Ongekidō Grand Master. Meanwhile, Zanki slays a band of Bakeneko as Ibuki arrives to take them out as well. But when the last Bakeneko escapes them, Decade kills it with the two groups as witness. Tsukasa visits Ibuki's school afterwads and talks with Ibuki and Akira about three special scrolls. Meanwhile, after failing to rob Hibiki as he takes his leave, Daiki is forced into becoming Asumu's mentor. Like Tsukasa, Daiki learns of the three scrolls of the Oni classes, and he convinces Asumu to become Hibiki's pupil again, before taking his leave to Zanki's dojo where he offers a proposition. Returning to find Hibiki and Asumu attacked by a Tengu, Kuuga attempts to battle the Makamou. At the same time, Natsumi encounters Narutaki as he reveals Tsukasa's actions actually doomed the worlds rather than saved them. When Kuuga is nearly killed, Hibiki assumes his Oni form to kill the Tengu before he suddenly transforms into the monstrous Gyuki. While this occurs, the Ibuki School and Tsukasa receive a challenge from Zanki's School and Daiki with the scrolls on the line. With them representing the two Oni schools, Decade and Diend do battle. But once Diend reveals his intentions to steal both scrolls, he summons Momotaros who attacks the Oni Kamen Riders until Gyuki storms in and overwhelms the Oni. The episode ends with Decade using Ryuki's powers to take on the Makamou.
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Journey's End
"Owaru Tabi"
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 * id="ep19"|19
 * style="text-align: left;"|"Journey's End"
 * Shōji Yonemura
 * May 31, 2009
 * colspan="4" style="border-bottom: 3px solid rgb(204, 204, 255);"|Using Ryuki's powers, Decade battles Gyuki while Ibuki and Zanki argue whose fault this was. When Akira and Todoroki join the fray in their Oni forms to save Asumu as he tries to protect them, with Decade joining them by using Den-O's Ax Form, they manage to defeat Gyuki. He runs off before regressing to Hibiki, and Yuusuke and Nastumi find him shortly after. Later that night, after talking to Asumu, Akira and Todoroki confront their mentors to put aside their differences, with Tsukasa supporting them. Ibuki and Zanki promote them to the role of new teachers of their respective schools. Meawhile, Hibiki reveals the nature of Gyuki to Yuusuke and Natsumi as Daiki arrives to claim the last scroll. Hibiki stops him and gives Daiki his Onsa to give to Asumu with a final request. The next day, after suffering a Narutaki-induced vision of the future resulting from their actions, Natsumi finds Daiki, who uses Asumu as his cover to steal the final scroll. But as Tsukasa arrives, Daiki evokes Hibiki's final change into Gyuki to Asumu's horror, and the thief leaves them. After learning the secret of the three scrolls to be all schools as one, Daiki returns to give Asumu the Onsa. Asumu becomes Kamen Rider Hibiki in order to honor his mentor's final request: slay the Makamou to free Hibiki's soul. However, Narutaki arrives on a giant Bakegani, with Todoroki and Amaki showing up shortly after. Once Diend destroys the scrolls, revealing that the true Ongekidō is all three styles in harmony, Decade regains Hibiki's powers. Decade, Diend, and the Oni all finish the Makamou off together. After Asumu and company thank Daiki for uniting the schools, Tsukasa and company return to Natsumi's world with Natsumi a bit worried.
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The Nega-World's Dark Riders
"Nega Sekai no Yami Raidā"
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 * id="ep20"|20
 * style="text-align: left;"|"The Nega-World's Dark Riders"
 * Toshiki Inoue
 * June 7, 2009
 * colspan="4" style="border-bottom: 3px solid rgb(204, 204, 255);"|With their tour of the nine Kamen Rider Worlds complete, the Hikari Studio group returns to their home world, finding it as it was before the monsters appeared. Tsukasa is the only one who feels something is not right and questions the reason for the journey. Before Yuusuke or Natsumi can attempt to answer, they encounter the violinist Otoya Kurenai, who thanks them for saving the world and tells Tsukasa that he earned a world of his own for his journey. As Natsumi goes out to see her TG Club friends and teacher for a high school reunion, Tsukasa and Yuusuke have a short encounter with Narutaki who congratulates him on getting his own world. Later, Tsukasa becomes the ten-thousandth customer in a restaurant and wins both a free meal as well as a vast fortune. Tsukasa enjoys the upper class lifestyle until he takes his leave during an arranged marriage meeting. Yuusuke is forced to take his place, but he runs off upon realizing that the women are actually monsters in disguise. Elsewhere, while hanging out with her TG Club friends, Natsumi tries to figure out where her friend Chinatsu is, and the TG Club members take the opportunity to run off, with the teacher attacking a couple as Alternative. Tsukasa runs into Otoya who mentions a treasure before transforming into Dark Kiva and challenging him, along with the other members of the TG Club who become Ryuga, Dark Kabuto, and Orga. With Diend arriving to back him up for this treasure, Decade battles Dark Kiva. When Decade attempts to use his Final AttackRide against Dark Kiva, the attack suddently cancels as he falls and reverts back to human. As the dark Riders leave, Tsukasa realizes that all of his Rider cards have turned black. Elsewhere, Natsumi is still searching for Chinatsu when she passes by someone in dirty and ragged clothing who turns out to be another Natsumi.
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The Walking All-Rider Album
"Aruku Kanzen Raidā Zukan"
 * -style="background: rgb(242, 242, 242) none repeat scroll 0% 0%; text-align: center; -moz-background-clip: -moz-initial; -moz-background-origin: -moz-initial; -moz-background-inline-policy: -moz-initial;"
 * id="ep21"|21
 * style="text-align: left;"|"The Walking All-Rider Album"
 * Toshiki Inoue
 * June 14, 2009
 * colspan="4" style="border-bottom: 3px solid rgb(204, 204, 255);"|After Tsukasa suddenly loses his powers, he learns from Kaito that he is actually in the World of Negatives. He later is seen by a talent agent and is offered to be signed onto his agency to become an idol. Although Yuusuke acts as the voice of reason, he gets caught up in the fame seeking as well. Meanwhile, after her school friends return while waiting for Chinatsu, Natsumi that suggests that they should dig up the "treasure" they buried together, only to find that a parking lot was built over it and learning that Chinatsu moved their treasure prior. Once, Tsukasa finds Natsumi, he attempts to tell her that they are not in the real world, but Natsumi refuses to accept this as she runs off to the TG Club's hideout where she also meets the World of Negatives's Natsumi. Confirming that Tsukasa is right and revealing that the world is a heaven for monsters with only a few survivors left in hiding. Furthermore, the Dark Riders had murdered the real TG Club members' Negative counterparts and assumed the males' identities with the other Natsumi the only survivor. It is then that the Dark Riders arrive to further prove the other Natsumi's words as they force her to dig up the Dark Riders' treasure she buried: the K-Touch. Otoya is prepared to give it to Tsukasa so he can become the Ultimate Rider until Diend intervenes by attacking the Dark Riders. Though Otoya offers him the world on a silver platter, Tsukasa refuses and he regains his powers. Using the K-Touch, Tsukasa transforms into Decade Complete Form, destroying Ryuga, Orga and Dark Kabuto with the powers of Ryuki Survive, Faiz Blaster Form, and Kabuto Hyper Form, respectively, as Otoya escapes destruction. After the other Natsumi bids farewell to her counterpart and Tsukasa, to whom she gives the K-Touch, the group returns to the Hikari Studio to resume their journey home with their next stop being Daiki Kaito's home world.
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Wanted: Diend
"Diendo Shimeitehai"
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 * id="ep22"|22
 * style="text-align: left;"|"Wanted: Diend"
 * Toshiki Inoue
 * June 28, 2009
 * colspan="4" style="border-bottom: 3px solid rgb(204, 204, 255);"|Arriving in Kaito's homeworld, the World of Diend, Tsukasa finds the world in peace and harmony, but with Kaito a wanted man. As Tsukasa assumes the role of a traveling salesman, he meets Kamen Riders Larc & Lance as they battle a Darkroach. After killing the monster, Tsukasa learns that the world's residents kill Kamen Riders. As Tsukasa and company meet the head of area management committee, Junichi Kaito, Larc and Lance battle the Darkroaches until they receive aid from Diend. Saving them from reinforcements, Tsukasa learns from Haruka and Shin that the world is ruled by the mysterious Fourteen who uses his Roaches to manipulate humans. Cornered by the Bossroach and his Darkroaches, the Kamen Riders battle the Roaches before Lance goes after Diend. While this occurs, Yuusuke is kidnapped by the Roaches to be conditioned into being a normal member of the World of Diend's society.
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End of Diend
"Endo Obu Diendo"
 * -style="background: rgb(242, 242, 242) none repeat scroll 0% 0%; text-align: center; -moz-background-clip: -moz-initial; -moz-background-origin: -moz-initial; -moz-background-inline-policy: -moz-initial;"
 * id="ep23"|23
 * style="text-align: left;"|"End of Diend"
 * Toshiki Inoue
 * July 5, 2009
 * colspan="4" style="border-bottom: 3px solid rgb(204, 204, 255);"|Nearly killed by Lance, Kaito is spared when Larc stops her partner as he reminds her that he is the reason that Junichi is under Fourteen's control. After escaping the angry mob, parting from Haruka and Shin, Kaito and Tsukasa find Natsumi who tells them that Yuusuke has been kidnapped by the Roaches before Junichi arrives to take her away to be brainwashed. After remembering the events leading to his brother's enslavement, Kaito is reluctant to fight as he and Tsukasa transform to follow Junichi, leaving the brain-washed Yuusuke behind. The next day, finding himself a wanted man as well, Tsukasa decides to help Kaito in spite of him refusing his aid. Using Kaito as bait to trade for the now brain-washed Natsumi, Tsukasa lures out Fourteen and Junichi. While Lance and Larc battle Glaive and the Darkroaches, Diend and Decade battle Fourteen as he reveals his true form as Jashin 14. Though overwhelmed, Decade assumes Complete Form and uses Armed Hibiki's power to destroy him. Though the Roaches fade away and the brainwashed humans return to normal, Glaive attacks Diend on his own free will for destroying the "peace" that Fourteen created for their world. With Decade holding Larc and Lance back, Diend battles Glaive on his own in a heated battle with neither wanting to kill the other. Tsukasa ends the battle, telling the brothers that they must protect each other no matter what the circumstances. Junichi leaves and Tsukasa and Kaito go off to the next world, one that Narutaki hopes will overwhelm Decade.
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Arrival of the Samurai Fighting Force
"Kenzan Samurai Sentai"
 * -style="background: rgb(242, 242, 242) none repeat scroll 0% 0%; text-align: center; -moz-background-clip: -moz-initial; -moz-background-origin: -moz-initial; -moz-background-inline-policy: -moz-initial;"
 * id="ep24"|24
 * style="text-align: left;"|"Arrival of the Samurai Fighting Force"
 * Yasuko Kobayashi
 * July 12, 2009
 * colspan="4" style="border-bottom: 3px solid rgb(204, 204, 255);"|Tsukasa and the gang arrive in a new world and discover it has no Kamen Riders, but instead has an entirely different kind of hero.
 * }
 * }