Gravemage Study{B}
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Enchantment
If you paid more black mana for Gravemage study than green mana, you cannot gain life.
Whenever a card is put into a graveyard, choose one:
Gain 1 life, or Lose 2 life and draw a card.
I think this is fairly balanced, and this mechanic plays heavily in the set I'm working on...
The concept here is forcing the power of hybrid cards down if they are played in monocolor decks, but UP if they are played as TRUE multicolor cards.
Here, you pay even BBG, and there's a huge drawback - but this could still see play in a monoblack deck.
My goal was to make at least a handful of "life for cards" effects; I think that card draw is

and I think this card fits the color pie rather well.
thoughts?