Rym, Myr Blightgrafter

Infect(This creature deals damage in the form of -1/-1 counters and poison counters)
Whenever Rym, Myr Blightgrafter or another myr creature enters the battlefield under your control, put a +1/+1 counter on it for each mana spent to cast it that was produced by a creature.
{2}: Target myr creature you control gains infect.