Zōken Matō, originally Makiri Zolgen, served as patriarch of the Zolgen family over five centuries before the Fifth Holy Grail War. His family originated in Kyiv before being driven out, leading them to adopt the name Makiri upon relocating to Japan. Zōken later changed the family name to Matou for concealment while maintaining a link to their origin through wordplay. As one of the three founding families of the Fuyuki Holy Grail War system, alongside the Einzberns and Tohsakas, Zōken proposed the Master-Servant framework. His initial dream was to create a utopia free from human suffering, fueled by idealism and deep admiration for Justeaze Lizrich von Einzbern, who became the core of the Holy Grail system. Her sacrifice devastated him. Over centuries awaiting the Grail's completion, his body deteriorated and his noble intentions warped into an obsessive quest for immortality, causing him to forget his original goal. Facing the Matou family's thinning magical bloodline in the decades preceding the Fifth War, Zōken manipulated the succession. Deeming his biological descendants—son Byakuya and grandson Shinji—insufficiently gifted, he arranged the adoption of Sakura Tohsaka, the Tohsaka family's younger daughter. Sakura endured brutal training and implantation with hybridized Crest Worms, parasitic familiars fused with tainted fragments from a previous Grail War. These worms drained her mana while feeding on her carnal impulses, effectively converting her into a vessel for Angra Mainyu, the Grail's corruption. During the Fourth Holy Grail War, Zōken implanted similar worms into his son Kariya, promising Sakura's freedom if Kariya won the Grail—a bargain Zōken never intended to honor. He revealed to Kariya that one Crest Worm had claimed Sakura's virginity, relishing his despair. In the Fifth Holy Grail War, specifically the *Heaven's Feel* timeline, Zōken emerged as a key orchestrator of chaos. He summoned the Servant "True Assassin" following Rider's defeat and exploited Sakura's connection to the "Shadow," a manifestation of the Grail's corruption within her. He disclosed Sakura's true nature and the Shadow's origins to Shirou Emiya in the Matou greenhouse, asserting that killing Sakura was the only way to stop it—a task he pressured Shirou to perform. Zōken clarified the Shadow was not his ally and he could barely contain it, despite having implanted it within Sakura years earlier. His manipulations extended to amplifying Sakura's psychological torment, feeding her feelings of isolation and jealousy. Zōken's physical form reflected his prolonged existence: a hunched, bald figure reliant on a walking stick, contrasting sharply with his youthful visage—a pale, red-eyed man with blue hair. His personality epitomized ruthlessness and cunning; he treated family members as expendable tools, openly mocking their suffering while pursuing immortality. However, his accumulated sins led to his downfall. In *Heaven's Feel*, Sakura crushed his true form—a Crest Worm hidden within her body—after he attempted to possess her. This act forced him to recall his original dream of saving humanity, and he accepted death.