Allure of the Unknown
Oracle Text
Reveal the top six cards of your library. An opponent exiles a nonland card among them, then you put the rest into your hand. That opponent may cast that card without paying its mana cost.
Reveal the top six cards of your library. An opponent exiles a nonland card among them, then you put the rest into your hand. That opponent may cast that card without paying its mana cost.
Even forgetting the ability that your opponent can cast this it is way worse than a draw 5 for 5 as losing the best card out of the 6 really hurts. Something like Tidings is just better for most decks.
Then taking in your opponent can cast the spell for free it becomes quite crap.
Only potential I see here is some sort of critical mass combo deck that would want this mostly for the combo turn and doesn't run spells they can give the opponent they would care about, only sorcery speed interaction for example.