Erebos, Bleak-Hearted

What’s more suiting for Theros: Beyond Death than the bleak-hearted God of the dead? A bit less like Greed this time around, though a little more things need to die to draw cards. That’s pretty easy for mono-black creatures to do, I think they die more than they attack.

Synergies

Urborg, Tomb of Yawgmoth + Cabal Coffers: If you’ve never seen mono-black generate more mana than mono-green this would be why they can do so. While not exactly necessary it turns any utility lands and Cabal Coffers itself into a swamp to add to the count.
Deserted Temple will help untap your Cabal Coffers for even more mana. It also works pretty well with Nykthos, Shrine to Nyx as a back-up.

Yawgmoth, Thran Physician + Blood Artist/Zulaport Cutthroat: Pay 1 life and sacrifice a creature then gain 1 life and an opponent loses 1 life. Draw a card and maybe put a -1/-1 counter on a creature. Seems like a good tradeoff to sacrifice a creature like Bloodghast or Reassembling Skeleton. You can find more of these tricks in decks with Yawgmoth as the commander but he also does great things with Planeswalkers and Proliferate.

Skullclamp + Bitterblossom: It could really just say Skullclamp + any creature but 2 cards each turn for 1 mana and 1 life is a very effective trade-off. Skullclamp is just very efficient which is well known but black is especially good at it. With Bloodghast as my prime example, clamp Bloodghast to draw 2, play a fetchland to return Bloodghast, clamp Bloodghast to draw 2, crack fetchland to return Bloodghast, clamp Bloodghast to draw 2. A synergy that can be pulled off very easily and often can net you 6 cards for 3 mana in one turn in mono-black.

Sheoldred, Whispering One + Sidisi, Undead Vizier: Pretty much Demonic Tutor each turn but that’s if you can keep Sheoldred on board and that doesn’t tend to happen. Sidisi is great in the graveyard though as it turns Animate Dead and my other reanimation spells into Demonic Tutor.

Combos

Exquisite Blood + Sanguine Bond: While looking for life gain effects and enchantment devotion this felt like the best place to bring this back. If your opponent loses life you gain that much, and then if you gain life your opponent loses that much life. Welp, guess you’re dead, well perhaps one at a time depending on multiplayer as Sanguine Bond only targets one opponent but it tends to be enough.

Mikaeus, the Unhallowed + Triskelion: Funny enough a combo that also came out of the original Innistrad block. Remove a +1/+1 counter from Triskelion and deal 1 damage to any target. Remove the rest to do the same but kill Triskelion itself with the damage. Undying trigger, Triskelion comes back and repeats until anything in your way is dead.

Nim Deathmantle + Ashnod’s Altar + Grave Titan: It’s really creature that can generate 3 bodies to sacrifice so Grave Titan fits the bill. Sacrifice the 2 zombies and Grave Titan to Ashnod’s Altar for 6 mana. Trigger Nim Deathmantle and pay 4 to bring Grave Titan back with its zombie friends. Net 2 mana into infinite mana. With infinite mana start keeping your zombies and just keep sacrificing and bringing back Grave Titan for an infinite army of zombies. Mikaeus and any non-human creature can replace Grave Titan in this combo for infinite enter the battlefield and die triggers. I would recommend anything like Blood Artist, Gray Merchant of Asphodel, or maybe Kokusho, the Evening Star.

Sensei’s Divining Top + Bolas’s Citadel + Aetherflux Reservoir: I’m naturally running the first two pieces anyway so may as well add Aetherflux Reservoir. Tap Top to draw, cast Top off the top with Bolas’ Citadel for 1 life, gain life equal to how many spells you’ve cast this turn from Aetherflux Reservoir, repeat. By the 18th time you do this, you should have gained 153 life and you can pay the 50 life to deal 50 damage to kill a few players. You also draw cards off of this so that’s a bonus

Fuel and Finishers

It’s really devotion and demons here because this is still and Erebos and besides zombies black is highly represented by demons.

Phyrexian Obliterator is enough devotion on its own to turn Erebos into a creature. This was the fact for his original Theros version and it’s still the case here. A terrifying card to deal with without some sort of removal that doesn’t use damage or at the cost of significant sacrifices.

Massacre Wurm is great for devotion but the enter the battlefield removal and life loss can keep some opponents in check. If someone drops a Blood Artist combo for instance that’s just a matter of who has more life at the time.

Razaketh, the Foulblooded will exchange 2 life and another creature as a sacrifice to tutor a card from your library to your hand. Really not a huge cost compared to the return. You could even pay another 2 life to Erebos for a card while you’re at it. Also, it’s an 8/8 Flying Trample creature so you can just beat your opponents with it.

Vilis, Broker of Blood will just give you a card every time you lose life at no extra cost! What a friendly demon. It comes with its own little removal but the -1/-1 isn’t as important as 2 cards for 1 mana and 2 life. Heck at worse I’ve targeted Vilis with his own ability. Vilis works with Yawgmoth, Razaketh, and of course our Commander Erebos. Another 8/8 Flying creature and another great target to reanimate.

Lastly Exsanguinate and Torment of Hailfire as two finisher options for all that generated mana. Exsanguinate may be the stronger option the more opponents you have and the more ways you can use the life you gain. Torment of Hailfire does more damage at once though but is dependent on your opponent’s resources, board state, and hand size.

Summary

Mono-black gets huge value plays fueled by card advantage, reanimation, tutors, kill spells, and some evil-looking finishers. All it’ll cost you is probably a ton of life making you walk close to the edge of death. It’s no risk, no reward though so go ahead and sell your soul to that demon! I wasn’t using mine anyways. This glass cannon approach needs some support and timing but if you like game interactions, asking life totals, and a bit of math then you might like this style.