GreyScale, king of calamity

Shroud, Indestructible, Vigilance, Lifelink
As an additional cost to GreyScale,
you lose 8 life and your next turn.
Creatures that block or
are blocked by this creature
dont untap during their controllers next
untap step, when this creature attacks all players discard 2 cards from their hand.
I will spare you, for a cost- GreyScale