The Chessmen of Mars - Edgar Rice Burroughs

In the fifth Barsoom adventure, Tara, the daughter of John Carter and Dejah Thoris takes center stage. Tara meets Gahan of Gathol, but she's not impressed. When Tara is stranded in an unfamiliar part of Barsoom and captured, Gahan sets out to rescue her. When he saves her, she doesn't recognize him as the prince she'd met earlier, so he introduces himself as a warrior named Turan. He's fallen for her, and is hoping to win her hand. Things take a turn for the worse when they end up in a game of Jetan (similar to chess) where living people take the place of the pieces in a battle to the death!