The Blood Witch

+1: Each opponent loses 3 life. Creatures you control have +X/+0 where X is the total amount of life lost this turn.
+2: Creatures you control have Double Strike and Menace until your next turn. Activate this ability only if a player lost life this turn.
-3: Until your next turn, whenever a player loses life, you may have that player lose twice that much life or draw 3 cards.