Being of Blood

As an additional cost to cast Being of Blood, pay X life where X is the mana spent to cast Being of Blood. Being of Blood enters the battlefield with X +1/+1 counters on it.
Whenever Being of Blood deals combat damage to a player, put a +1/+1 counter on it.
Pay X life: Remove X +1/+1 counters from Being of Blood. Being of Blood gains flying until end of turn. Any player may activate this ability.