Vindicare Assassin

Whenever you gain life, put two +1/+1
counters on Vindicare Assassin.
{w}{b}, Remove six +1/+1 counters from Vindicare Assassin: Exile target creature.

"Exitus Acta Probat; The outcome justifies the deed."
— Dictatus Vindicare, the maxim of the Vindicare Temple