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Boast — {1}: Exile the top card of your library. You may play that card this turn. (Activate only if this creature attacked this turn and only once each turn.)
If you don’t play the card by the end of the turn, it will remain exiled. Boasting again on a future turn won’t let you play that card.
Playing a card this way follows the normal rules for playing the card. You must pay its costs, and you must follow all applicable timing rules. For example, if the card is a sorcery card, you can cast it only during your main phase while the stack is empty.
The card you exile with the boast ability is exiled face up.
Under normal circumstances, you can play a land this way only if you haven’t played a land yet that turn.
