Mazgul, Celestial Gyre

This spell cannot be countered.
Trample, lifelink, deathtouch, indestructible
Permanents you control gain "Sacrifice
this card: put X +1/+1 counters on Mazgul, the
Celestial Gyre, where X is this card's converted
mana cost."
At the beginning of your upkeep, if this creature
has 30 or more power, you win the game.