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When this card enters the battlefield, each player
exiles the top card of their library face-up.

During each player's turn, that player may play a
land or cast a spell from among cards exiled with
this card, and they may spend mana as though it
were mana of any color to cast that spell. When they
do, if the player that casted it didn't own the card,
the cards owner creates treasure tokens equal to that
cards mana cost. If there are no more cards exiled
with this card, shuffle this card