Valdor, Thane of Doom

+2: Until end of turn, whenever a creature you control attacks, you may have target player put the top card of their library into their graveyard.
-3: Target creature gets +X/+X or -X/-X until end of turn, where X is the number of cards in target player's graveyard.
-10: You get an emblem with "Whenever a card is put into an opponent's library from anywhere, that player loses 1 life and you gain 1 life."