Exquisite Blood

Whenever an opponent loses life, you gain that much life.

Dead of Winter

All nonsnow creatures get -X/-X until end of turn, where X is the number of snow permanents you control.

Destroy target creature or enchantment an opponent controls. You lose life equal to that permanent's mana value.

Whenever a creature deals damage to you, destroy it.

As an additional cost to cast this spell, sacrifice a creature.
Add {B}{B}{B}{B}.