Don't know if this helps, but Gray Merchant of Asphodel and Whip of Erebos is a pretty nasty combo.

Ok Shazica thanks for the tip and the +1

Balustrade Spy take those out, and instead more removal! like Geth's Verdict or Dismember . Or Tragic Slip against indestructible. Sideboard the Lifebane Zombie . Is this more budget or?

It's not budget and I don't know much about black control so all suggestions are greatly appreciated.

Take out Diabolic Tutor run Thoughtseize or Inquisition of Kozilek . Mono Black is great for ripping their hand apart. Damnation mass removal. Phyrexian Obliterator a beautiful card that if not answered with removal, can easily win you the game. Liliana of the Veil

I love the obliterator I can't believe I forgot he existed XD

Go for the Throat instead of Murder .

And Gray Merchant of Asphodel .

Dash Hopes for sideboard in modern is all I have to say

Also, Geralf's Messenger is a beater.

Source: I played against this deck yesterday and was totally impressed

If you're going for control, you could try Inquisition of Kozilek and Surgical Extraction .

Wrench Mind seems like a bad card to me honestly... Maybe finishing your set of Lily's and playing some number of Smallpox to help your tron matchup would be better. I might play Bile Blight in place of Go for the Throat , it's really good against Affinity whereas Go for the Throat doesn't do squat. You might want to consider Dark Confidant and Gatekeeper of Malakir to help you get some awesome value

Muchos gracias

@corythackston Why is Wrench Mind a bad card? if your playing again affinity or tron its terrible so i can see it being a sideboard card but if your playing against a deck with little to none artifacts its a modern Hymm to Tourach...which is the best discard spell ever printed

nice +1 if you have the cash id get Mutavault in here and heros downfall should be at 4

Pack Rat could work well in here...

Maybe in place of Painful Quandary

this is more of a discard deck than mono-black control either way Mutilate maybe?