Keiran, Ace of Spades

+1: Choose an opponent. They reveal the top card of their library. You may exile that card. If it has a mana cost, they lose 2 life.
-2: A target player discards two cards, and you gain life equal to the total converted mana cost of both cards.
-7: You get an emblem stating, "At the beginning of each opponent's upkeep, they take damage equal to the mana cost of each card in their hand."