Kozniak, Disciple of Mana

+1: Add X mana of any colour to your mana pool. Exile a creature you control with converted mana cost X.
0: Creatures you control gain hexproof until end of turn. Put a -1/-1 counter on target permanent for each creature given hexproof this way.
-8: You gain life equal to the total number of enchantments, sorceries, and instants in all graveyards.