Greven, Predator Captain
{3}{B}{R}
Legendary Creature -- Phyrexian Human Warrior
5/5
Menace
~this~ gets +X/+0, where X is the amount of life you've lost this turn.
Whenever ~this~ attacks, you may sacrifice another creature. If you do, you draw cards equal to that creature's power and you lose life equal to that creature's toughness.