This deck is based around the mechanic of milling yourself to cause you cards to gain power and cost less.
Key cards:
Whip of Erebos is one of the main wincons of this deck. It can bring back a powerful Ghoultree or Kessig Cagebreakers for one turn, but that will usually be all that you need. Lifelink on all of your creatures will also give you amazing life gain so that you can afford to take some damage and preserve your creatures.
Artful Dodge
+
Jarad, Golgari Lich Lord
wil, make a Ghoultree or Sewer Nemesis Deal massive direct damage. Because Artful Dodge will likely be in your graveyard, the flashback makes it the perfect card.
Graveyard Fillers:
Early-mid game cards that will fill the graveyard to cut a path for your powerful finishers.
Jace's Archivist
Hand refill
Mirror-Mad Phantasm Insane mill
Satyr Wayfinder Bonus Ramp
Finishers:
Cards that will easily dismember your opponent in late game when you have enough creatures in your graveyard.
Ghoultree 10/10 for 1 green mana? An obvious choice.
Sewer Nemesis Wait... all cards in my graveyard, not just the creatures?
Jarad, Golgari Lich Lord Not only does he get into the high numbers, but he can deal direct damage, fill the graveyard, and return from the dead.
Wreath of Geists
a creature with the power of Jarad, Golgari Lich Lord for 1 mana? I'll take it.
Kessig Cagebreakers -IMPORTANT- you want this card in your graveyard. It is next to useless when played from your hand. The most effective to play it is to bring it back with Whip of Erebos for an OTK.
Mid game:
Cards to keep you alive while you "ramp" up for a huge Sewer Nemesis or something like that. These cards can occasionally kill an opponent before the last phase of the plot if done right.
Sidisi, Brood Tyrant Zombie army!
Skaab Ruinator cheap as chip$
Jarad, Golgari Lich Lord + Sewer Nemesis
even though they are used for late game finishers, you should have them early and ready to strike without summoning sickness.
Well, thats my deck, comment and +1 if you like it!