Avatar of Woe: Large evasive body, repeatable removal, and typically discounted since we fill graveyards fast. Great finisher that rarely disappoints.
Big Game Hunter: Spot removal on a small creature. Can be played off a discard trigger, fed to a sac outlet or Skullclamp, or just used as a chump blocker. Great creature to sac in order to flip Liliana since by he's usually done his job once he ETB.
Blood Pet: Cheap body that sacrifices itself to provide a small mana boost. Primarily used to flip Liliana.
Bloodghast: Skullclamp's best friend and strongest member of the unholy trinity. Bloodghast is the king of sacrifice fodder. If you need to sacrifice a creature this is always a good option.
Bone Shredder: Cheap spot removal on a creature. The echo is actually great because we can choose to let Shredder die in order to flip Liliana.
Carrion Feeder: Cheap Sacrifice outlet that eats fodder or itself to flip Liliana. Can save your board from a mass exile or tuck effect like Terminus or Merciless Eviction.
Carrionette: It's a cheap sacrifice fodder that becomes removal in the graveyard. The nice thing is that exiling it is not a cost, it's part of the resolution so if your opponent pays the 2 Carrionette stays in the graveyard. It didn't seem very powerful at first, but it's usefulness has come to surprise me over and over again.
Containment Construct: This gives every card in the deck better Madness. The most egregious part about this card is the fact that exiling your cards is optional. If you can play the card you discard later just exile it and play it later in the turn, if you cant throw it to the Graveyard as normal.
Coffin Queen: Repeatable reanimation from any graveyard. This might be the only 1/1 I would never consider Skullclamping.
Disciple of Bolas: Our deck runs tons of Sacrifice fodder. This guy lets us draw cards off of them.
Fleshbag Marauder: This guy is an all star, and is routinely looped to act as a mini board wipe. This guy is one of my all time favorite cards.
Gray Merchant of Asphodel: This is our strongest win condition, and easily my most common method of ending the game. Once our opponents don't have a hand my most common path to victory is playing/reanimating Gary and then sacrificing him so I can reanimate him again and drain my opponents to death.
Merciless Executioner: Fleshbag Marauder 2: Electric Boogaloo
Mikaeus, the Unhallowed: This guy provides tons of value. He's an evasive 5/5, and anthem, and provides resilience to board wipes. Be careful though as any nonhuman you steal from an opponent's graveyard will Undying back to its owner, not to you.
Mindleech Ghoul: Flips Liliana and forces a discard.
Mindslicer: Were you having trouble with pesky opponents not letting you empty their hands. Mindslicer makes it easy. Bonus points for flipping Lilly with his death.
Nether Traitor: Second member of the unholy trinity. Traitor is scrifice fodder that reanimates itself, which is great for Skullclamp abuse. Shadow's a cool ability to have as well on the off chance you run into someone who's trying to use Dauthi Trapper to voltron people out with their commander or Infect damage.
Nezumi Graverobber
: Cheap body, reusable graveyard hate, and transforms into reusable reanimation. This guy was hailed as a commander staple back in the early days of the format, but I don't see him very much anymore. He's just as good as he's always been, and really should see more play.
Pestilence Demon: Solid Finisher with a respectable 7/6 flying body. Also acts as a mana sink and a board wipe
Plaguecrafter: Fleshbag Marauder 3: Tokyo Drift
Puppeteer Clique: All around great value creature, that synergizes with our discard effects. Becomes nearly impossible to actually kill when we have our Mikaeus, the Unhallowed.
Razaketh, the Foulblooded: This guy’s insane. Huge evasive body, repeatable tutoring, and a sac outlet that requires no mana or tapping investments. You should win most games Razaketh resolves.
Rune-Scarred Demon: Demonic Tutor attached to a 6/6 flying. If you can't figure out why we play this, a mono black deck might not be the deck for you.
Sheoldred, Whispering One: One of the best black Finishers in the format. She reanimates, she kills creatures, and she's an evasive 6/6.
Shriekmaw: Spot removal on a creature. His evoke + Terror is why we run him since evoking him will flip Liliana.
Smothering Abomination: Provides us with card advantage and an easy way to flip Liliana. It's also a 4/3 Flying which is quite respectable and can get some work done. Be aware, because of devoid Abomination is not actually black so it can't be sacrificed to Soldevi Adnate.
Soldevi Adnate: This is a gem I found in a bargain bin one day, and it's been the MVP of countless games since. It both Flips Liliana and has the ability to provide absurd levels of mana early on in the game. At worst Adnate sacrifices itself to provide a small burst. At best we're sacrificing bombs like Rune-Scarred Demon & Gray Merchant of Asphodel for insane amounts of mana that we can use to repeatedly reanimate them for their ETB triggers.
Tergrid, God of Fright
: This card is disgusting, and generates so much value off a single Liliana +2. Completely game ending if you can resolve a Death Cloud without killing her.