Essence Thief

As an additional cost to cast Essence Thief,
sacrifice a creature.
When Essence Thief deals combat damage to a
player, that player chooses one of the following:
-Defending player loses 3 life.
-Defending player discards a card.
-Defending player puts the top 3 cards of their
library into their graveyard.
"Life is precious. Sell it to the highest bidder."