10 years ago, a Pegasus by the name of Max Million invented the game of Duel Monsters, known in certain circles as simply Yugioh. Soon after its creation, it took off faster than any known product before it, with ponies from all ages picking it up and playing the game. Twilight Sparkle, introverted disciple of princess Celestia, decides that she would not involve herself in the card game in order to advance herself in her studies.

However, on the week of the Summer Sun Celebration, Twilight Sparkle is not only given the tasks of overseeing the Celebration and making friends, but also to participate in the tournament that would take place in the morning of the raising of the sun. As time grows closer to the Celebration, she finds some startling evidence connecting the cards to events that took place over one-thousand years ago, although information is scarce.

What is the connection between these cards and history?