Xilleus, Nessian Calamity

Xilleus enters the battlefield with X +1/+1 counters on it
Whenever a creature with power four or greater enters the battlefield put a +1/+1 counter on each creature you control.
{1}{r}{g}: Remove X +1/+1 counters from Xilleus, then it deals X damage to target creature or planeswalker.