Kain, Guardian of Balance

: Whenever one or more creatures you control deal combat damage to an opponent, put a loyalty counter on Kain, Guardian of Balance.
-2: Deal 2 damage to any target or the next creature you cast has Bloodthirst 2. If a creature died from this effect, you gain 2 life.
-4: Until end of turn, when a creature you control deals combat damage to an opponent gain life equal to the damage or put a +1/+1 on it.