So, I've been seeing a LOT of people posting MTG_Joe's MBC list today, and I took a lot of inspiration from it as well, so I thought I'd throw my list up too.  I've always loved playing heavy control, and mono-black, while not super strong right now has a lot of tools to really make things work.  I'll try a quick write-up for now and see where this list takes me from here.

Creatures

Kitesail Freebooter - One of my edits to the list.  I love the 2 toughness on him, as well as the flying.  Pulling problematic cards out of your opponents hand is REALLY good too.  There's nothing quite like stealing removal from lists that are typically short on it and just hovering around the battlefield with the stolen card.

Blacklance Paragon - Still one of my favorite removal spells currently in standard.  It doesn't always hit very well (looking at you Azorius Flyers), but when it does it really takes people by surprise.  The lifegain on top of the surprise block is also very good at keeping you alive.

Murderous Rider - Removal spell + a 2/3 lifelink blocker.  It's as good as everyone has seen.

Solemn Simulacrum - Sad Robot is critical to MBC.  Pulling lands and drawing off of chump blocks always feels really strong in control.

Massacre Wurm - This card...  I'm not totally sold on it yet, and since it runs as a 1-of in the list I don't have enough experience to really say if it earns it's spot yet.  This may be an easy cut if I can find something more functional.

Artifacts

Mazemind Tome - 4-of.  Scry, draw and lifegain all in one card.  It's really good you guys.  You should play with it.

Instant / Sorcery

Agonizing Remorse - Never underestimate knowing what your opponent has.  I typically find it better to throw them off curve with effects like this, but there's a strong argument for also hitting some late game cards early to make sure you don't need to deal with them later on.

Extinction Event - I don't like Ritual of Soot.  It doesn't hit enough late game, and it comes down at the same time as EE does.  This may not hit aggro quite as hard as Ritual does, but it will hit more.  In my experience you really want to off smaller targets with spot removal as it is (i.e. Eliminate).

Grim Tutor - Finally a list that I can run Grim Tutor in and not feel like I'm losing tempo.  It's better to hold off on this until the game state hits a critical point and then pull out a specific answer.  Paying life sucks.  Don't do it until you have something worth paying 3 life for.

Grasp of Darkness / Eliminate - Both serve the same purpose really.  Early game threats need to be taken care of cleanly and these do the job well.  Grasp over Heartless to get around puppers.

Planeswalkers

Liliana, Dreadhorde General - She makes a very appealing target for Grim Tutor.  She's really good and deserves her high price tag.

Ugin, the Spirit Dragon - Our top end of the deck.  He comes down hard and almost always leaves some serious damage in his wake.  I've been able to ult him a bit more consistently with this list as well, so that's a thing.

Note: I know the original list runs multiple Ugin the Ineffable, but I feel like there's room for other cards over what is essentially a card draw engine that can moonlight as removal.  I may find room for him later on though, especially as the list becomes a bit more refined.

Lands

So, I decided to throw my own spin on the mana base with this deck.  24 lands is a BIT on the light side, but with Sad Robots acting as a fetch, and Fabled Passage effectively thinning the deck to a 57 card list I feel pretty confident in it.  There are games where I've stalled out, but with the majority of cards coming down at 4 CMC or less, it's a little bit less of an issue if you do stall for a couple turns until you can ramp with robots.  3 Temples and 2 Triomes round it out to help set up draws and give me a little bit more late game gas.  Jury is out on whether this is a better way to go than with the original mana base.

Let me know if you have any suggestions!

Edit 1: -1 Agonizing Remorse, -1 Grim Tutor.  +2 Doom Whisperer.  Agonizing Remorse didn't always feel super good to play midgame with opponents having multiple serious threats in hand, and Grim Tutor, while helpful, didn't feel impactful enough to justify running 2 copies (1 is fine, especially with the other singletons in the list).  Doom Whisperer is a very competitively costed card with great stats and Surveil is a fantastic ability.  He also contests the board and can act as a bit of a finisher.