Ethra, Purging Wing

+2: Gain control of target creature an opponent controls until end of turn.
-1: Draw two cards, you cast one without paying its manacost, if you do, exile the other.
-10: Gain control of each nonlegendary creature, you get an emblem with "Whenever you cast a spell, create a 3/3 Ethra Servant with deathtouch."