Rule 103.6

In a Planechase game, the starting player moves the top card of his or her planar deck off that planar deck and turns it face up. If it's a plane card, that card is the starting plane. If it's a phenomenon card, the player puts that card on the bottom of his or her planar deck and repeats this process until a plane card is turned face up. (See rule 901, "Planechase.")

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