Historical Rules · 13 October 2023
Rule 406.3a
Official source text from the 13 October 2023 Rules release
A card exiled face down has no characteristics, but the spell or ability that exiled it may allow it to be played from exile. Unless that card is being cast face down (see rule 708.4), the card is turned face up just before the player announces that they are playing the card (see rule 601.2).