Actor: Hassei Takano
For Kanzaki had been content to ignore his peaceful ways before, but now Tezuka was getting in the way of the game. With Shinji's drive he was a force to be reckoned with. They managed to bleed off Ren's suicidal rage, intrigue Jun, and might possibly have turned the tide of battle to living. Oddly, the first thing Kanzaki tried was giving him an extra edge in the battles. He gave him a Survive card. Tezuka never once considered keeping it. He gave it to Ren. That sealed his fate, for Kanzaki made the decision to take Tezuka out of the game. First he sent an assassin Tezuka had a personal grudge against, Gold Thunder.
Tezuka went into a rage and fought the monster with a ferocity that frightened Shinji and, after he destroyed it, he explained why. He was never meant to be a Kamen Rider. Kanzaki had chosen Yuichi Saito, a concert pianist and Tezuka's dearest friend. They had been walking together one winter's night when a madman (three guesses who) came raging and attacked them in passing. He smashed Yuichi down. The injuries inflicted cost Yuichi his fine motorskills in his hands, ruined his ability to play. Kanzaki approached him and gave him a card deck, promising that if he was the last Rider his hands would be restored. He must have thought about it for some time. He'd bound a monster... and he called Tezuka to him, told him the whole story. Told him he refused to fight to be the final Rider. I think he just could not stand to become a murderer. His decision was absolute, and upon making it he became a target. Gold Thunder took advantage of his distance from his deck, grabbed and pulled him into the Mirror World. Tezuka fought to save him but just wasn' strong enough. And all that was left was for Tezuka to take up the mantle of Raia. All he wanted was to seek justice for Yuichi, and to protect other people from the same fate. He had no other reason to be a Rider. No prize or wish he wanted to win. And without that kind of drive, he did not feel impelled to try to win.
So when Oja's Final Vent would have destroyed Ryuuki, Raia acted. He knocked Ryuuki away and placed himself in the path of death. His armor disintegrated. Ryuuki took him out of the Mirror World, but wounds suffered there remain and Tezuka died in Shinji's arms. But at some point, he told Shinji to watch out for Yui.