Divulged Divination

Exile the top four cards of your library face down. Until the beginning of your next upkeep, target opponent may look at and cast cards exiled with Divulged Divination and they may spend mana
as though it were mana of any color to cast those
cards.
At the beginning of your next upkeep, put all
cards exiled with Divulged Divination into your
hand.