Koschei, the Immortal

Undying
When Koschei, the Immortal enter the battlefield,
each creature you don't control get -6/-0 until
your next turn.
When a creature you don't control enter the
battlefield , put two +0/+1 counter on Koschei,
the Immortal.
At the beginning of of your upkeep, put X +1/+0
counter on Koschei, the Immortal, where X is his
toughness.