Yuji Kiba

"Do you know? A dream is the same as a curse. Those who fail are forever cursed. Or so I hear..."
 * firstepisode = The Start of a Trip
 * lastepisode = Kamen Rider 555: Paradise Lost
 * numberofepisodes = 48 (555) 2 (Movies)}}

- Kiba when explaining to another Orphnoch about dreams right before attacking him

Yuji Kiba (木場 勇治) was one of the primary characters that appeared in Kamen Rider 555. He mostly served as one of the antagonists and occasional protagonists in the series. He was a young man who becomes the Horse Orphnoch (ホースオルフェノク) after dying as a result of a car crash, although he lived in a comatose state for two years. He has assumed a total of three Rider forms: two in the series (Faiz and Kaixa) and one in Paradise Lost (Orga).

Series
Originally human, Kiba became a Natural Orphnoch after dying within two years when he was in a coma as a result of horrific car crash which killed his parents. Once revived, Kiba was astonished by the horrific changes from his parents' death to overhearing that his uncle forsaken him and sold his family's company. Though it got worse when Kiba learns that his girlfriend Chie Morishita left him for his cousin named Kazuaki Kiba, he lost control when he confronts the new boyfriend as he assumes his Orphnoch form to kill him in a maddened rage before realizing what he had done and attempts suicide, finding himself in a Smart Brain owned mansion and meeting Smart Lady, explaining his current status. When he is called by Chie later, he is heartbroken when she names him the culprit in Kazuaki's murder, outrunning the police before he murders Chie out of scorn. After finding Yuka, Kiba meets with Smart Brain's temporary CEO Eiichi Toda, who reveals more information of the Orphnoch and Smart Brain's goal. After hearing the genocidal intent, Kiba quickly comes to deplore the organization's tactics and resolved to become an Orphnoch who will protect humans and fight Smart Brain. However, Kiba becomes a rival of Faiz, fighting him every time they encountered one another until they learned each others' true identity and intent.

Unfortunately, Kusaka uses the Faiz Gear to trick Kiba to think that Takumi is a bad guy. He also lies to Takumi that Kiba is the one who stole the Faiz Gear, making both Kiba and Takumi become rivals once again. However, after knowing that Takumi is Wolf Orphnoch, Kiba starts to reconcile with Takumi. Unfortunately, Takumi loses his confidence and gives the Faiz Gear to Kiba for a short time. Kiba becomes Faiz for some time until he saves Takumi from his near death from Kyoji Murakami. He later gives back the Faiz Gear to Takumi.

After he believed Yuka to have been killed by the police, Kiba turns against his ideals and eventually replaces Murakami as the chairman of Smart Brain. He later kills Kusaka and claims his Kaixa Driver. Kiba eventually fought Takumi, and Kiba was defeated. However, Takumi didn't finish him, since Kiba was still a human. Kiba then revived his faith in humanity again and helps Takumi and Mihara fight the Arch Orphnoch. In the end, Kiba was mortally wounded by the Arch Orphnoch, grabbing the monster to allow Faiz to kill them both, though only the Arch Orphnoch barely survived.

Paradise Lost
In the film, Kiba was the primary user of the Orga Gear. In the events of the film, Yuji Kiba is brainwashed by the Smart Brain corporation and is chosen to be the user of the Orga Gear, allowing him to transform into Kamen Rider Orga. The Orga gear was recorded as the fifth Rider Gear created by Smart Brain, after the Faiz and Kaixa Gears were stolen by the humans and the Riotrooper gear had undergone mass-production. Created alongside the Psyga Gear, the Orga Gear is regarded as a "perfect" gear, and therefore it can only be worn by Orphnochs. Kamen Rider Orga has a more ornate appearance than any of the previous Gears, the Rider form having robes made of Soul Foam for a majestic appearance. Orga is armed with the Orga Stlanzer sword which he uses in the Orga Slash Extreme Charge. He is sent to fight Kamen Rider Faiz after Psyga is defeated. Faiz is finally able to defeat Kamen Rider Orga with Blaster Forms Rider Kick, but does not kill him. Instead, Orga dies while trying to hold off the Elasmotherium Orphnoch so Faiz can destroy it, after Takumi finally gets through to him and reminds him of what Smart Brain really stands for and what his true values are.

Kamen Rider Taisen
Kiba appears as the Horse Orphnoch in a flashback fighting Kaixa while Faiz fought the Arch Orphnoch in a retconned depiction of Masato Kusaka's death seen in Heisei Rider vs. Showa Rider: Kamen Rider Taisen feat. Super Sentai. Unlike the original, Kusaka died after being defeated by the Horse Orphnoch.

Kamen Rider 555 video game
The Horse Orphnoch is one of several Orphnoch who are playable in the Kamen Rider 555 video game.

Kamen Rider Battride War
The Horse Orphnoch appears as a boss in the video game Kamen Rider: Battride War.

As Kamen Rider Faiz

 * SB-555B Faiz Driver - Faiz's transformation belt.
 * SB-555P Faiz Phone - The control unit of the Faiz Gear.
 * Faiz Mission Memory - A small metallic card key containing the information of the Faiz Armor.
 * SB-555C Faiz Shot - Digital camera-shaped knuckle-duster.
 * SB-555B2 Faiz Pointer - A laser pointer which enables to produce an energy drill deathblow.
 * SB-555H Faiz Edge - A lightsabre-like sword that can be stored in Autovajin.
 * SB-555W Faiz Axel Watch - A stopwatch that enables to gain access to Axel Form.
 * Axel Mission Memory - A small metallic card key containing the information of the Faiz Axel Armor.
 * SB-555V Auto Vajin - Faiz's motorcycle that can transform in a robot-like Battle Mode.

As Kamen Rider Kaixa

 * SB-913B Kaixa Driver - Kaixa's transformation device.
 * SB-913P Kaixa Phone - The control unit of Kaixa Gear.
 * Kaixa Mission Memory - A small metallic card key containing the information of the Kaixa Armor.
 * SB-913C Kaixa Shot - Digital camera-shaped knuckle-duster.
 * SB-913B Kaixa Pointer - binocular-shaped pointer which enables to produce an energy drill deathblow.
 * SB-913X Kaixa Blaygun - A special weapon that is both a pistol, a dagger and a lightsaber.
 * SB-913V Side Basshar - Kaixa's sidecar motorcycle that can transform in a robot-like Battle Mode.

As Kamen Rider Orga

 * SB-000B Orga Driver - Orga's transformation device.
 * SB-000P Orga Phone - The control unit of Orga Gear.
 * Orga Mission Memory - A small metallic card key containing the information of the Orga Armor.
 * SB-000S Orga Stlanzer - Orga's main sword weapon.

Rider Cards

 * Kamen Ride: Orga: A Rider Card containing the power of Kamen Rider Orga, possessed by Kamen Rider Diend. It one of the eight cards used by Diend Complete Form. It summons Kamen Rider Orga.

Portrayal
Yuji Kiba is portrayed by Masayuki Izumi (泉 政行). As Kamen Rider Kaixa and the Horse Orphnoch, his suit actor was Makoto Ito (伊藤 慎).