The Relentless

When the Relentless enters the battlefield, sacrifice a creature. If you sacrifice a Zombie in this way, target opponent loses 3 life.
Pay 3 life: Return the Relentless from your graveyard to your hand.
"Look at all these people. Fractious and warring in life, divided by loyalties and scruples. In death, they have found perfect peace with one another. Isn't it just so beautiful?"