The Sledgehammer, known as Strong Ishijima in the Japanese version, is a character in the Yu-Gi-Oh! ARC-V anime, the former champion of the Pro League.
In the dub, Sledgehammer's voice resembles Arnold Schwarzenegger.
Pre-Arc League Championship
Sledgehammer promoted the Leo Institute of Dueling in its commercial. Sledgehammer's manager, Nico Smiley, arranged an Action Duel between Sledgehammer and Yusho's son, Yuya Sakaki. As the announcements for the Duel begin, Yuya appeared to be nowhere to be found, causing Sledgehammer and many of the crowd to think that Yuya was as cowardly as his father. Yuya then showed up behind him, dressed as a harlequin, forcing the audience to point out Sledgehammer's challenger to him. Sledgehammer was displeased with Yuya's attitude, thinking that he was being disrespectful, and allowed Yuya to take the first turn in the Duel. Yuya immediately Summoned and began to ride away on "Performapal Hip Hippo," much to Sledgehammer's displeasure as he remained on one of the towers of "Castle of Chaos." Sledgehammer brought out his ace monster on his first turn, "Battleguard King," but Yuya swiftly used Action Cards to dodge and endure the repeated attacks. Yuya then proceeded to call out his own ace card, "Odd-Eyes Dragon", and used Action Cards that he'd spotted while running around the arena to pay for the cost of his "Wonder Balloons", something Sledgehammer picked up on. Yuya attempted a One-Turn Kill, but Sledgehammer used his own Action Card to prevent the damage, and in his next turn, reduced Yuya to 400 Life Points and restored his own. He appeared to have the match won, but then Yuya performed a Pendulum Summon and Summoned three monsters at once. Sledgehammer was shocked that it could have happened, but Nico Smiley pointed out that Yuya's Duel Disk had accepted it, so there was no error. Yuya then proceeded to wipe out all of Sledgehammer's Life Points by supporting his "Odd-Eyes Pendulum Dragon" with his other monsters, knocking Sledgehammer backwards.
After his loss, he chose to step down as champion and went overseas to train.
After Z-ARC's defeat and the Standard Dimension being reborn into the "Pendulum Dimension", Sledgehammer is seen watching Yuya's Duel against Jack Atlas. He applauded when Yuya won and watched Yuya and Declan's Action Duel. He was happy when Yuya won the Duel and witnessed Zuzu Boyle's revival.
Sledgehammer plays a "Battleguard" Deck, mainly focused on Summoning his ace monster, "Battleguard King". He supports it with cards such as "Battleguard Howling" and "Battleguard Rage" which he combines with "Battleguard Magic" to replenish his Life Points.
- Unlike the first opponents of previous series where they eventually become either frenemies or close allies to the main protagonist, The Sledgehammer never appears again after his loss to Yuya.