You've probably worked it out already, but we want to get Pandemonium into play and then cast or reanimate Phyrexian Dreadnought twice for 24 damage.
Pandemonium is, of course, our win condition and Phyrexian Dreadnought and Aboroth are the creatures to trigger it. I can hear you laughing at poor Aboroth, but it's simple math. 12 + 9 = Dead. And, while we never hope to need to, we can cast it with our Lotus Petals and it's a little easier to get out than Crash of Rhinos (the only other creature in these blocks that can combine with Phyrexian Dreadnought for 20 or more damage).
We have a couple of options to find the pieces we need in Vampiric Tutor and Buried Alive. Vampiric Tutor can get anything we need, which is usually Pandemonium. Buried Alive puts our creatures in our yard which, with all of the reanimation, might as well be in our hand. Not to mention that when the game goes long 3 Dreadnoughts in the graveyard with a Living Death in hand is very exciting.
The rest of our deck is dedicated to bringing our creatures back from the dead to strike again. Reanimate and Shallow Grave are straightforward reanimation for 12 damage. Living Death makes for much bigger swings when needed (or for fun), and Corpse Dance is repeatable reanimation for the long game (assuming your opponent doesn't have a win condition and you get to the long game).
Rounding out the non-basic slots in the deck are Cinder Marsh, Rocky Tar Pit, and Lotus Petal for getting the we need, and Dark Ritual for fueling the turn 1 victory.