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Ranma ½, season 5 episode 15 «Shogi Showdown»: air date July 19, 1991. Episode overview, season trailer and the cast of Ranma ½.
A master of the mysterious martial arts of Battle Shogi seeks out Genma, demanding a rematch for the defeat that cost him the respect of his wife. When Genma cunningly wins again, the man decides to turn the entire lawn into a gigantic shogi board.