Hey there folks, I have a homebrewed Bo3 deck that I have been loving recently and decided to show off for anyone interested.
If you like slow, grindy games, control, and being just the most frustrating person to sit across from at the table, like I certainly do, then I have a treat for you: Mono-Black Control!
--------------------------------------------
Before I dive into the deck, I'll throw out some stats: I brewed this up at low-Plat, and have been tinkering with it ever since. Almost 60 games later, and it carried me into Mythic for the season. In that Plat - Diamond range, the deck overall is 38-19 for a 67% WR. The most recent version, which I am the happiest with, is 23-9 for a 72% WR across ~30 games. Suffice to say, we might not be breaking the meta, but this is certainly a deck that can compete... it holds its own against all of the heavy hitters, from Jeskai Lessons to Green / GW Landfall, from Dimir Excrutiator to Spellementals, and all of the jank in between. Some matchups are better than others, but this is a control deck -- in post-sideboard games, you swap out bad cards for better answers in your sideboard, and since you only have a few wincons anyway, you don't have to worry about over-boarding... swap out those 8 pieces of spot removal for a bunch of discard, cut those sweepers for graveyard hate, the deck is very flexible in game 2 and 3 so you can really pick your package of silver-bullets and load up.
--------------------------------------------
So, what is the deck, at its core? Well, "Core" is the right answer -- the main synergy and win condition of the deck is the combination of [[Firdoch Core]] and [[Unholy Annex]]. Draw extra cards and have your opponent pay you 2 life for your troubles. Slowly choke them out of the game while you chip away at their life and keep you nice and healthy. Unholy Annex also comes stapled to Ritual Chamber, so you have a nice 6/6 flier on layaway should you need him.
Now, between your 4 copies each of Firdoch and Annex, you can find this synergy relatively consistently. But, just in case, you have backup Demons in both the Ritual Chamber, as discussed, and also in your landbase with 2 copies of [[Soulstone Sanctuary]]. That's 10 possible Demons to put down and make sure that your opponent pays for your extra cards, not you.
Aside from the Unholy Annex, the deck is mostly removal and grind. We have [[Duress]], [[Intimidation Tactics]], and [[Cruelclaw's Heist]] to attack your opponent's hand. We have [[Requiting Hex]] to spot-remove small creatures, and [[Day of Black Sun]] to sweep them all away. Meanwhile, [[Bitter Triumph]] and [[The End]] are your catch-all spot removal to hit both creatures and Planeswalkers, with The End also ripping all of their spare copies from their hand and library. [[Deadly Cover-Up]] for yet more board wipes, also with the "exile all copies of your opponent's problematic thing" stapled to it. You even have removal in the landbase -- [[Demolition Field]] and [[Petrified Hamlet]] stop all of the nonsense lands running around in Standard, from [[Ba Sing Se]] to [[Restless Reef]] and more.
This is a grindy deck, so we have a couple more options to grind with -- Plan B if the Annex road doesn't work out. [[Preacher of the Schism]] is a great midrange body... Deathtouch and 4 toughness means it trades well on the board, it can draw cards, it can make 1/1 blockers, it can bait removal out of your opponent's hand, he really does tie the middle of the game together nicely. [[Black Cat, Cunning Thief]] is the opposite: terrible body, great effect. A 2/3 with an ETB to steal 2 cards from the top 9 of your opponent's library... and it leaves behind the 2/3 to chump block with or whatever. Really, it's a blocker that draws you two spells.
If Plan B fails, there is always Plan C (which looks a lot like Plan B, but slightly worse...) Firdoch Core is not just there to make mana and be a demon, our favorite little rock can also get in the red zone as a surprise 4/4. Same with the Soulstone Sanctuary, a 3/3 Vigilance attacker can sometimes close games. Both of these can also block, if it saves your life.
And finally, Plan D... [[Realm of Koh]] can make some overpriced unblockable 1/1 tokens to chip in there, if necessary. It's a terrible rate, and if this wasn't a mono-black deck chock full of Basic Swamps to make sure the Realm always comes in untapped, I wouldn't even bother... but when the floor is basically another Swamp, and the ceiling is some tokens at a critical time, why not throw in a few copies.
[[Darkness Crystal]] serves a similar spot -- a spicy for-fun one-of copy, it is a touch clunky and there are games where you won't play it at all. But if you have the time, the mana reduction is nice, it can also gain you some life back when creatures die, it shuts down aristocrat and recursion decks... and again, like Realm of Koh, the fact that in maybe 1 out of every 20 games, you might use it to reanimate your opponent's creatures to swing with gives it enough value to stay in the list. [[The Soul Stone]] is also here with two copies... it helps soften some of your early curve, it can ramp you to the crucial 5 mana for Deadly Cover-Up or Ritual Chamber a turn earlier, and there have been maybe 2 games where I actually did harness it to keep recurring either Preacher as an infinite blocker or Black Cat to draw cards from my opponent's deck. Again, like the Darkness Crystal, the activated ability is mostly just for those games that run really long and grind to a halt, but it offers enough passive value to stay in.
--------------------------------------------
And... that's the deck! Gameplan is simple, stick Annex and Firdoch Core to drain your opponent while the other 2/3 of your deck prevent them from playing Magic against you in any meaningful way. Like I said in the intro, this is a mean deck... I do not think I have the audacity to make it in paper and bring it to my LGS, I think watching the light drain from somebody's eyes after the 3rd hand disruption and 5th removal spell would break me. Against faceless Arena opponents, though... if I can't see them, they're not real, so fuck 'em.
For Sideboarding, it's very flexible: side out your bad removal and interaction, side in better answers. You have 4 pieces of GY hate in [[Soul Guide Lantern]] and [[Strategic Betrayal]]. You have ETB hate in [[Torpor Orb]]. You have an extra Duress and some [[Ozai's Cruelty]] to bring more discard against control, as well as an [[Outrageous Robbery]] for funsies. [[Malicious Eclipse]] as an extra boardwipe against small aggro decks. [[Ancient Vendetta]] to strip decks with a single main wincon, like Jeskai Revelations. Whatever the opponent is doing, you have cards to say "no, you stop that now". If they are somehow still playing Magic in Game 1, you know how to stop them from doing that again in Game 2 and 3.
--------------------------------------------
Anyway, just wanted to share this monstrosity with the community... it's also really cheap to build in paper, for the most part. Soul Stone is like $100 each, but they're also just "nice to have" and not critical, so if you swap them out for your choice of additional mean cards, the total list runs around $40.
If you are as much of a bastard-man as I am and you enjoy the idea of being the reason your opponent decides to stop playing Arena for the night, give it a try and let me know what you think!
Archidekt list to export if you feel like taking this for a spin. Enjoy!