Lashwrithe Whip of Erebos or Sword of Light and Shadow ...cut arena down to 2 and add the 4th Lilly. Gatekeeper should probably be Geralf's Messenger and gatekeeper isn't really worth running. I'd advise the 4th Bloodghast

I run a similar deck sometimes Funeral Shroud

@APPLE01DOJ thanks for the suggestions they really helped me shape this deck and the budget version.

Ghoulcaller's Chant is a great way to get back your zombies and abuse Korlash's ability. You could also consider a couple Infernal Tutor to grab more Korlash, removal, whatever.

No Phyrexian Obliterator????

@strikegently I don't like Phyrexian Obliterator in this type of deck for a number of reasons. For one obliterator spends most of its time just being a 4 drop wall, which is not the way my deck is supposed to defend. Instead it is supposed to permanently answer problems with removal While still being aggressive. Also obliterator is often just a big dumb 4 drop 5/5 with no ETBs. Thus the value I get out of it low especially if it's immediately responded to with an answer like Dismember. The deck is built around hard to kill creatures with low cmc costs that provide value and obliterator just doesn't help here. While obliterator may be good against eldrazi decks and big zoo, the rest of the decks in modern simply ignore obliterator with evasion, a massive package of removal ( basically causing me to give my opponent a time walk), or some so sort of combo. Now if there was a better mono black ramp card than Nykthos, Shrine to Nyx I might try Phyrexian Obliterator again, but for now he is a very mediocre card that requires something like Arena to be more useful.

awesome deck, i think you could add in Nykthos, Shrine to Nyx and Gray Merchant of Asphodel for a sort of mana accelerant to be able to put down 2-3 turns worth of mana in 1 go, and also finish off a game with 1 swift move.