polukranos enters the battlefield with six +1/+1 counters on it. it escapes with twelve +1/+1 counters on it instead.
if damage would be dealt to polukranos while it has a +1/+1 counter on it, prevent that damage and remove that many +1/+1 counters from it.
1bg: polukranos fights another target creature.
escape—4bg, exile six other cards from your graveyard.