I would consider cutting the westvale from your mana base and adding in Nykthos, Shrine to Nyx. Nykthos will speed you up considerably. Also consider swapping Diregraf Ghoul for Cryptbreaker. same cmc, but Cryptbreaker offers a lot more value.

Thanks for the suggestions mattm68w! I will definitely look into adding those. Also thanks for the plus 1!

You can't cast your Prized Amalgam cards?

TooMuchTalent, I use Cryptbreaker to discard the Prized Amalgam. Using Gravecrawler or Relentless Dead, I can bring it in without casting it.

Gravecrawler has to be put into the graveyard and, Relentless Dead has to die for it to bring anything back.

Too many endless ranks of the dead)Why only 3 lords? I running 8 and it works great.Why no cheap removals like tragic slip (fatal push).And finally may be you need some more turn 1 zombies, like diregraf ghoul/dread wanderer?

Filipp_bor, Tragic Slip looks like a good cheap inclusion. Fatal Push, I agree I should invest in. Lord of the Undead would be good. I do have a play set of Diregraf Ghoul but, I took it out. I could cut out 2 Endless Ranks of the Dead, I just like having 4 in there.

I didn't try 4, but imo 2 is enough)

If you interest, you can see my zombie deck