Rumpelstiltskin's Deal

Reveal the top 3 cards of your library then exile them facedown in a random order, target opponent then names a card. Reveal the top facedown card exiled with Rumpelstiltskin's Deal. If the revealed card is the one named by the opponent, they get an emblem with"add one mana of any color to your mana pool during each of your main phases". If the revealed card is not the one named by the opponent, search that opponent's library for a creature card and put that card onto the battlefield under your control.