Nebulae dragon

Nebulae dragon enters the battlefield with
X +1/+1 counters on it. Nebulae dragon is
immune to deathtouch, and ignores indestructible
effects. Whenever Nebulae dragon attacks,
sacrifice 3 creatures. If you can't, pay 10 life.
{u}{u}{w}{w}{b}{b}{r}{r}{g}{g}:Nebulae dragon gains
+0/+x, where x is Nebulae dragons current
toughness, double strike, and supernova (If this
creature is destroyed, it deals dmg to target player
equal to the number of cards in your hand).