Pyro

At the beginning of your upkeep, remove all -1/-1 counters from creatures you control. You gain 1 life for each counter removed this way.
Whenever Pyro blocks or is blocked by a nonartifact creature, put a -1/-1 counter on that creature.
{1},{t}: Pyro deals 1 damage to target attacking or blocking creature and puts a -1/-1 counter on it.
I don't want to light a flame in your heart;
I just want to set the world on fire.