Arkveld, White Wraith

Flying Sacrifice an artifact: Arkveld, White Wraith gains first strike until end of turn. Whenever Arkveld, White Wraith deals combat damage, put that many +1/+1 counters on it (It must survive to get the counters) If a creature dealt damage by Arkveld, White Wraith would die this turn, you gain life equal to that creature’s toughness.