Ok. So here's how it works. The characters are Fair Folk out in the Wyld, competing through dream-stories created out of the Wyld's essence.
The players create Magic decks, but change the flavor and names of the cards ahead of time. The flavor must match the mechanics and color of the card, but is otherwise open.
Then you play a game of Magic. After each turn, the player who's turn it was describes what happens in the story based on the events of the turn.
Creatures are actual creatures that can come into play, but spells (such as enchantments, sorceries, and instants) can either represent A) Magic used by characters in the story, B) Spontaneous magic in the story, or C) Other events that match the story.
At the end of the game, the winner narrates the ending.
Oh, and at the start of the game everyone agrees on starting points (such as premise) for the story and states the goals of their Fair Folk.