Karthiz, the mawing flame

Trample.
Karthiz, the mawing flame enters with X +1/+1 counters where X is the Mana spent to cast it.
Whenever a -1/-1 counter is
Put on a creature
that doesn't have a -1/-1 counter, summon a "fumespitter" token onto the battlefield that says "sacrifice this creature and put a -1/-1 counter on target creature" onto the battlefield.