Mirko Vosk, Soul Hunter

Flying, Deathtouch
Whenever Mirko Vosk, Soul Hunter deals combat
damage to a player, that player mills cards from
their library until they mill a land card.
If one or more creatures were milled this way,
place a +1/+1 counter this creature.
If one or more non-creature spells were milled
this way, this creature deals damage equal to its
power to target creature that player controls.