Zakusa Ishigame, whose surname combines the kanji for "stone" and "turtle," is a member of Team Blackout. He possesses pale skin and shoulder-length wavy white hair, typically secured in a topknot with a hairpin, and keeps his eyes habitually closed. He favors traditional Japanese clothing. Initially appearing laid-back and absent-minded, Zakusa expresses himself through eccentric mannerisms and a passion for painting, perspectives shaped by his upbringing as a potter's son and his studies in Japanese art. This artistic demeanor conceals a dangerous, aggressive streak from his delinquent past, triggered by provocations like his cards being scattered by helicopter wind or threats to Wonder Hill; Tomari and Danji help manage this duality.

His history includes an arrest by Tomari for delinquency. She brought him to Wonder Park, taught him to play Vanguard, and facilitated his integration into Team Blackout. Competing in the Deluxe tournament's Group A, Zakusa suffered losses to Yu-yu Kondo, Raika Koshiba, and Taizo Kiyokura, barring his advancement. Later recruited by the Uniformers under the alias "Shirogane," he became an antagonist. During this phase, he rebuilt his deck and achieved victories: off-screen against an unnamed fighter and Haruka Soukawa, on-screen against Taizo Kiyokura, and ultimately against Yu-yu Kondo. He also participated in the Divinez DELUXE Arc against Megumi Okura with an unknown result.

Zakusa wields a Brandt Gate deck focused on the Cardinal ride line. He employs "World" Set Orders to establish conditions like "Dark Night" and "Abyssal Dark Night," activating normal unit effects and calling Shadow Army Tokens. An improved version later features Cardinal Dominus, Orfist Regis. His deck composition includes triggers: Ameliorate Connector, Patrol Robo Dekarcop, Cardinal Draco Barbizonde, Cardinal Prima Nabilem, Cardinal Draco Enpyro, and Star Dragon Deity of Infinitude, Eldobreath. He retained this trigger lineup after joining the Uniformers.

His fight record details early losses in will+Dress Season 1: off-screen defeats to Yu-yu Kondo and Raika Koshiba, plus an on-screen loss to Masanori Iseki. As Shirogane, he secured multiple wins, culminating in the victory against Yu-yu Kondo. Within Team Blackout during will+Dress Season 1, Zakusa served as Yu-yu Kondo's number two, mirroring roles like Haruka's support of Mirei, including checking on Yu-yu after defeats. His journey traces a path from delinquent past to Team Blackout member, then to Uniformer antagonist, marked by personal and competitive evolution.