After witnessing the death of Jun Shibaura at the hands of Dark Shinji, Kimura and Ren are shocked. Ryuga then attacks Kimura, wanting Kimura to die for him, saying that if he wins the Rider War, he can escape to the real world and exist as a real being. Ren transforms into Kamen Rider Knight and uses Trick Vent to distract Ryuga. Ryuga swiftly defeats the Trick Vent copies, only to find out Ren and Kimura have already escaped.
In the real world, Another Ryuki is still wreaking havoc, killing numerous police officers. A man whose face is hidden in a white cloak uses a crystal orb to absorb the life essence of the lives the Another Rider has claimed. Another Ryuki reverts back to Tatsuya Kano and asks the man in white when he may be able to revive Sara, the man replies it would be soon enough. Meanwhile, in a hospital, a dying Sara is still pleading for Tatsuya to stop his rampage.
Back in the Mirror World, Kimura manages to flee, only to be found by a group of monsters. Too exhausted and wounded to transform, he is eaten alive by the trio.
Ren is riding his motorcycle, wanting nothing to do with the events anymore. However, he is surprise-attacked by three Mirror Monsters, regaining his memory upon being hit in the head by one of them. Finally realizing that it has been Shinji's voice that tells him to stop the Rider War all along, Ren transforms and slay the monsters.
Elsewhere, Asakura, vexed because he has nobody to fight with, vents his anger on Goro. He threatens to kill Goro if Goro does not find an opponent for him right away. Just at that moment, Dark Shinji comes and offers to "play" with Asakura. Finally happy with a chance to fight, Asakura transforms and charges at Dark Shinji. The two fought a brief while before Knight appears and strikes Ouja, remarking that Kido's opponent is not the madman but him. Ouja is amused and begins fighting Knight. Knight tells Ouja that he is merely wanting to die, then uses his Final Vent on him right after, fatally wounding Ouja, forcing him to flee. As Goro finds his "master" on the verge of death due to the attack, he uses the Magna Visor in human form to shoot at Ouja. It is revealed here that Goro's memory about the past is also intact, and that he only agrees to serve and follow Asakura earlier so that he may have a chance to kill him. He has been loyal to Shuichi Kitaoka all along, and he wants to fulfill his late master's wishes to end Asakura once and for all. Goro transforms into Zolda and uses his Shoot Vent to attack Ouja, wounding him even more. Engulfed in flames, Ouja still defiantly charges at Zolda and uses his Veno Saber to slash him in the chest, then stab through his abdomen. The two combatants are subsequently forced out of their transformations. Asakura lies on the ground unconscious. Goro, thinking that he has fulfilled his master's wish, starts to disintegrate because of Ouja's inflicted stab wound.
Ren is still trying to make Shinji remember the past, and reveals to him that the voice inside his head is Shinji's, which keeps telling him to stop the war. Nevertheless, Dark Shinji states it is useless to try and bring his real counterpart back, as he no longer exists. Ren shouts at him, telling Shinji to come back, otherwise, he would have to kill Shinji. The two transform and begin a duel, with Ryuga being the winner. As Ryuga is about to land the killing blow on Knight, the real Shinji begins to surface and forces Ryuga to stop the attack. Ren says that Dark Shinji can never win because he does not understand the bond between him and the real Shinji. Knight then strikes Ryuga, forcing him back into human form. Ren, thinking that Shinji has returned to normal, de-transforms and comes by his side. However, Dark Shinji is still in control of the body, he grabs his Black Drag Saber and fights Ren in human form. Just as the two are struggling against each other, Asakura, also in human form, wields his Veno Saber and interrupts their fight. Asakura prepares to stab Shinji with Veno Saber, only for Ren to shield his friend from the attack, mortally wounded as a result. Asakura, still wanting to fight more and more, screams in dissatisfaction as he disintegrates.
Shinji, who has now subdued his dark counterpart for good and has his memory of the past restored, comes at his dying friend's side. Ren recounts the events of the past Rider War, saying that Shinji dies before him at that time. Ren tells Shinji to live this time. Shinji pleads Ren not to die, but to no avail, as the wound, he has received does not permit him to live any longer. As Shinji is the last man standing, Sara proclaims him the winner of the Rider War and pleads him to stop Tatsuya. She offers Shinji her life and opens a mirror for him to escape to the real world.
Shinji returns to the real world and transforms into Kamen Rider Ryuki to fight Another Ryuki. The two seem to be evenly matched. Shinji reveals to Tatsuya that Sara has offered him her life earlier to stop Tatsuya and that Sara has used her life essence until the last moments of her life just for Tatsuya to become a good person again. The Another Rider falls on his knees in distraught and sadness. The mysterious man in white appears before the two, voicing his disapproval of Shinji's interference, and subsequently uses his powers to knock Shinji back.
Sougo and Geiz come by Shinji's side, to comfort him. Shinji mistakes Geiz for Ren, much to the future Rider's confusion. Shinji asks Sougo to take care of things for him from that time on. Sougo and Geiz realize that they have unlocked the Ryuki and Knight Ridewatches, respectively. He then lets the duo fight Another Ryuki while deciding to go somewhere else. The man in white uses the life essence in the orb to revitalize Another Ryuki, but Sougo assumes Decade Armor Ryuki Form and soundly defeats the Another Rider, destroying the Anotherwatch in the process. However, their victory is short-lived, as the man in white reveals himself to be Kamen Rider Odin - The most powerful Rider in Kamen Rider Ryuki. He transforms and overpowers Geiz and Zi-O with Sword Vent and teleportation abilities.
Meanwhile, Shinji is on his way to a hospital. He recounts his last moments with Ren earlier: The man who keeps appearing in his dreams from day one is indeed Ren all along. Ren asks Shinji to come and check on his fiancee - Eri Ogawa - as he wants to know whether she's happy or not. Shinji finds Eri, now a nurse, taking care of a child patient. She is shown wearing three rings - the very same rings that Ren always carries with him in the previous Rider War. As Eri is happy with her job, Shinji leaves the hospital.
Zi-O and Geiz are still being overwhelmed by the might of Kamen Rider Odin. Odin states that the two cannot defeat him as long as he still possesses the three Survive Cards. Odin says the "game"/The Rider War will be restarted and over and over again until the end of time. The Ryuki and Knight Ridewatches start to glow, and Geiz notes that the two must be used simultaneously for their full powers to be utilized. Sougo agrees as the duo both activates their finishers. Odin also activates his Final Vent to counter them, but he is defeated by the combined effort of the Riders. Before he disintegrates, he utters one final word: "Yui...".
A visibly sad Shinji is seen walking about while reminiscing his final moments with Ren once more: Before dying, Ren is certain that Shinji and he will meet each other again, in a place without fighting. When that time comes, Ren asks whether the two can continue "annoying" each other like they used to do. Shinji tearfully agrees, just as his friend starts to vanish in his very arms.
Shinji pulls out the Dragreder and Darkwing Advent Cards from his pockets and lets them fly away into the air. As the cards disappear up high, Shinji continues his walk down the road...
Episode Tropes:
- Bittersweet Ending: Another Ryuki is finished, but Sara died giving the last of her strength to send Shinji back to the real world. Also, every Rider from the Rider War, minus Shinji, is dead with no Reset Button to bring them back but at least Shinji is finally free from the burdens of being a Kamen Rider. He tosses the Dragreder and Darkwing Advent cards into the air, where they fly off and dissolve into light.
- Eaten Alive: Kimura's final fate as three Buzzstingers get the jump on him.
- Fake Defector: It turns out Goro has been faking his allegiance to Asakura and waited for the moment to get the drop on the latter in Kitaoka's honor.
- A Good Way to Die: Goro dies satisfied that he was able to avenge Kitaoka's death at Asakura's hands.
- "I Know You Are in There Somewhere" Fight: Ren battles Dark Shinji in an attempt to liberate the actual Shinji from his control.
- Impaled with Extreme Prejudice: Ren is stabbed full-force by the Veno Saber trying to protect Shinji.
- Invincible Villain: Subverted. Kamen Rider Odin is hyped up to be exactly as game-breaking as he was in the show. But, once the Ryuki and Knight Ridewatches resonate, two of his Survive Cards disintegrate. This allows Zi-O and Geiz to finish him off.
- The Nameless: It isn't revealed what the user of Odin really looks like, much less their name. They utter Yui's name as they die, implying it may have been Shiro Kanzaki or yet another human being manipulated by him.
- Only One Me Allowed Right Now: Averted. Ryuki and Another Ryuki are able to clash on practically-even footing without the time-altering nature of the Anotherwatches coming into play.
- Rasputinian Death: Asakura survived Knight's Final Vent and a blast from Zolda's Shoot Vent, and is still standing until he stabs Ren with his Veno Saber. That's when he finally succumbs to his wounds.
- Time-Delayed Death: Already weakened by Ryuga beforehand, Asakura receives a critical attack from Zolda that kills him. It isn't until he stabs Ren that his body gives out and he disintegrates.
- True Final Boss: Kamen Rider Odin after Another Ryuki was defeated for good.
