Duel Monsters. The favorite pastime of many of Canterlot High's students. The HuMane 7 are some of the best players in the school.

School is out for summer, and Discord Corporation, a new stockholder for Duel Monsters, is hosting a citywide summer tournament. But the company president has a more sinister agenda. He wants Sunset's magic, and he's willing to kidnap Twilight and hold her hostage to get the Equine girl to participate in his tournament. Sunset will have to face many tough opponents and fight for the one she loves. (I suck at summaries. ^^;)