Taiga was originally a renowned genius radiologist at the Seito University Hospital, who is capable of detecting and removing cancer cells in an instant. At the time of Zero Day, he was chosen to be a Kamen Rider for CR after accidentally discovering the essence of Bugster Viruses through conventional methods. Despite having passed the examination to become a Kamen Rider, Taiga refused to take it until the death of his coworker Maki forced him to accept the offer.
When the Proto Bang Bang Shooting Gashat began to hurt Taiga's mind and body in the process, Taiga was temporarily prohibited from transforming. Despite this, Taiga was still adamant on saving his patient's life, to the point where he ignored orders to stand down and reclaimed the Gashat and Gamer Driver from Kuroto Dan, just as the latter had planned.
Ultimately, Taiga fell from grace by this side effect after failing to defeat Graphite, a Bugster that spawned from Saki Momose. His defeat cost Saki her life, and his doctor's license was subsequently revoked for disobeying orders, with the Ministry having decided that Taiga had become overly obsessed with the power of the Gashats. Saki's boyfriend, Hiiro Kagami, has since held a grudge against Taiga and blames him for Saki's death. Taiga would eventually lose all hope in saving others as a doctor and a Kamen Rider, eventually going on to believe that clearing the games was the only important thing to him. To his shock, the side effects of the Proto Gashats had caused his hair to turn white as well.
Taiga observed Ex-Aid's first fight against the Bugster from afar, using a rifle scope as a means from seeing afar. He then mimicked shooting Ex-Aid.
He purchased his own Gamer Driver and Bang Bang Shooting Gashat from Genm Corp. with large piles of cash. When complimented by Kuroto Dan, he simply said that Dan needed a large amount of money to make new games.
With Gamer Driver in hand Taiga kept a low profile only acting when he thought an opportunity presented itself he could swipe another gashat or two but no real opportunities arrived until the Power Riders started to show up, seizing the opportunity after Extreme defeats brave and kills Daemon, Paladin, and Laser he offers 100,000 yen (1,000 USD) to Extreme to get him level X variants of the others gashats and to buy off the ones she had already created. Taking advantage of Kelly’s lack of knowledge of the exchange rate of USD to yen. Now in possession of lvl X variants of Bang Bang Shooting, Giri Giri Chambara, Jet Combat, and Bakuso Bike Taiga has once again gone dark as he prepares for his next battle with Graphite, unaware that Saki has resurfaced inside the Bugster.
Convinced he was seeing another showdown with Graphite on the horizon, he would stick to laying low and trying to gather as many resources he needs to get the job done. This would however lead him to cross paths with Saki, aware that some part of her bad been brought back but is otherwise convinced it's Graphite pretending to be her. Not helping matters was that this happened to be right after she had made a scene trying to appeal to a brainwashed Emu and Nico, further convincing the disgraced radiologist that it's just Graphite projecting in this instance. He'd eventually get onto the case of Evan Carson after a nasty run-in with Kamen Rider Genm.
These kinds of circumstances would eventually lead him to reluctantly enter a partnership with Blecker and the Hojo siblings, seeing the adverse effects her Dungeons and Dragons Gashat is having on CR, especially with his massive reservations on Emu's competence after the Evolt fiasco. Eventually, team Blecker have managed to develop a proper treatment to the virus that didn't require the direct intervention of the Riders, leaving only his doubts on if Saki is the real deal after her resurrection as Team Blecker are planning to get Lexx on-board for wider treatment, especially in relation to the strength of Level 0 and how it can affect Riders like him.
Taiga was originally a kind doctor who valued the lives of his patients and did whatever he could to make them smile. However, becoming a Kamen Rider would eventually change him, with his defeat at the hands of Graphite being the turning point, causing him to give up all hope.
As a result, he has become bitter, arrogant, and selfish, holding almost absolutely no concern for protecting individuals; he cares only about his obsessions of both collecting Gashats and achieving his revenge on the Bugsters. Clearing all the ten games became his main drive for fighting, and as such he would resort to any form of dirty tactics just to claim all of the Gashats. He would later view Saki's death with disdain as well, using that just to taunt Hiiro.
Taiga especially holds a strong animosity against Graphite, who cost him both his medical license and his credibility as a doctor. He would constantly find a way to settle things once and for all with Graphite. His hatred of the Bugster overshadows any concern for a patient's well-being. For him, the battles are competitions with his fellow Riders.
Despite willing to use dirty tactics to win, Taiga does have a sense of fair play as he did not try to take Emu's Gashat by force, nor did he think that Kiriya Kujo would take the Mighty Action X Gashat from him before even winning their bet. This however, didn't stop him for being provocative to fellow Riders. Similarly, while he kidnapped the Collabos Bugster to blackmail Ex-Aid and Brave, he did not demand them to directly surrender their Gashats to him, but instead wanted to win them through a fair battle.
Name: Taiga Hanaya
Age: 29
Birthday: [Redacted] 1987
Gender: Male