Black Sacrement

Offering 3 (When you cast this card you may exile 3 permanents in addition to paying its mana cost.)
Each opponent sacrifices half of their permanents,
or puts the top ten cards of their library into their graveyard.
If this cards Offering cost was paid, draw a card
for each creature that was put into a graveyard
this way and add {b}{b} to your mana pool for each
land that was put into a graveyard this way.