Yup, it's the progenitor of Lhurgoyfs. Seen as one of the more powerful creatures from early Magic, this card has quite the reputation for being badass, but does it deserve all the praise? Well, at base level, it's a 0/1 for 4 which, needless to say, is really bad. However, it does improve greatly if there has been a lot of creatures killed in the game. It's major advantage over cards like Boneyard Wurm or Revenant is that is counts creature cards from all graveyards, not just your own. In multiplayer, this card becomes a tank late game because of this. However, it can work against you as well. Against a reanimator deck, this card probably won't get that high up in power unless a lot of your creatures are dying. A burn deck with very few creatures will also leave this card lacking in power. It also doesn't have any type of evasion like Trample, so a 1/1 token can easily be thrown in front of it. To be completely honest, I prefer Magnivore or Tarmogoyf over this. Magnivore has haste and a lot of people use sorceries in their decks, so it'll get fairly big and Tarmogoyf costs 2 less and relies on variety rather than sheer numbers (sure, he has a max power level, but he'll probably reach it quicker than this card).
Pros: Gets really big with creature deaths
Cons: Relies on creatures dying (and staying dead), no evasion