Yui Kanzaki/World of If

is Shinji Kido & Ren Akiyama's accomplice who is aware of the existence of the Mirror World and the Rider Fight who becomes .
==History==
===World of If===
After Shinji becomes Ryuga, he starts to rampage in the Mirror World. Hideyuki Kagawa, as Alternative Zero shows up with an army of twelve Alternatives in order to destroy Ryuga. As they prepare to attack Ryuga, Yui Kanzaki shows up. Kagawa laughs; Yui is the source of all their troubles and if she dies everything will end. They attack her instead, but Ryuga, having his sanity returned shields her. He reverts to Shinji and dies. Kagawa is shocked that there's a Kamen Rider who would give up their life for someone. Yui says she has a favor to ask of him.
With the Survive Card in his hand, Ouja, as the final Rider, stands before Odin. While in the middle of the battle, Alternative Zero jumps in and join forces with Ouja in order to fight Odin. Ouja activates his Final Vent; Venoviper transforms into a bike and charges at Odin, spitting poison along the way. A moment before it hits him, though, he activates his Time Vent and vanishes, then reappears on Venoviper's seat, behind Ouja and strikes him quickly.
Right before he dies, Asakura sees Odin's face, through the hole in his helmet melted through by Venoviper's poison, revealing Ren's face. The mask completely crumbles away and Ren comes back to his senses. He looks down at his body and realized what happened. After Eri died, he quits being a Kamen Rider while throwing away Knight's Advent Deck. While wandering at the streets, a man shows up and gives him an Advent Deck and turned him into Odin's puppet.
With a full anger, he yells out the name of Shiro Kanzaki as he appears and laughing in glee. Now that Odin is the victor of the Rider Battle, and now he can finally grant Yui a new life. Ren notices the Alternative Zero and has a weird feeling about him as he heads over and yanks out the deck. Turns out it was Yui all along. She revealed that she borrowed it from Kagawa to stop Shiro and reaches out to him. But he has no body, and can't grasp her hand. Yui faints and dies as Shiro failed to grant her a new life and mourning her death. 
==Alternative Zero==
Alternative Zero
;Rider Statistics
* Rider Height: 190 cm.Hobby Japan. (2007). S.I.C. Official Diorama Story: S.I.C. Hero Saga. Vol. 2. p. 63. ISBN 978-4894256309.
*Rider Weight: 93 kg.
;Ability Parameters
*Punching Power: 15 t. 
*Kicking Power: 22.5 t.
*Maximum Jump Height: 50 m.
;Special Attacks
*Dragon Rider Kick: 400 t.
In the S.I.C. Hero Saga, Yui became the Alternative Zero in order to confront Odin.
==Contract Monster==
*Psyco-Rogue
==Equipment==
*Advent Deck - Transformation device and Advent Card holder
*V Buckle - Transformation belt
*Advent Cards - Trinkets that enable a Rider to summon Contract Monsters, access equipment, and use special abilities
*Slashvisor - Alternative Zero's Visor that enables him to use Advent Cards
==Vehicles==
*Psycoroader - Serves as Alternative Zero's motorcycle
==Appearances ==
* Kamen Rider Ryuki
**Kamen Rider Ryuki:World of If
==See also==
===Footnotes===
==Navigation==
Category:Ryuki Characters
Category:Ryuki Riders
Category:S.I.C. Hero Saga Riders
Category:Heisei Era Riders
Category:Debatable Riders
Category:Female Riders