Saer'khon, The Ravager

Immortal (Spells and abilities cannot reduce
this creature's toughness less than 1)
Whenever a creature dies you may pay {r}{g}{w}. If you do, put a +1/+1 counter on
each non white creature you control.
Feast on the fallen, grow stronger, defeat more enemies.. a vicious cycle of life for Saer'khon