Rule 406.3

Exiled cards are, by default, kept face up and may be examined by any player at any time. Cards “exiled face down” can’t be examined by any player except when instructions allow it. However, if a player is instructed to look at a card and then exile it face down, or once a player is allowed to look at a card exiled face down, that player may continue to look at that card until it leaves the exile zone or is part of a pile of cards that are shuffled, even if the instruction allowing the player to do so no longer applies.

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