This one may have come up for some of you in the past couple of weeks since M15, and it may very well happen to you in the future if it hasn't! is a common Black creature that eats dead guys. More specifically, when it enters the battlefield it'll exile a creature card from any graveyard you so choose, and gain you life equal to that creature's power. The bigger the meal, the bigger the reward for you! Now, it's generally pretty easy to figure out how much that'll be- you just look at the card.