Gray Merchant of Asphodel

When Gray Merchant of Asphodel enters, each opponent loses X life, where X is your devotion to black. You gain life equal to the life lost this way. (Each {B} in the mana costs of permanents you control counts toward your devotion to black.)

Vampire Lacerator

At the beginning of your upkeep, you lose 1 life unless an opponent has 10 or less life.

Ob Nixilis's Cruelty

Target creature gets -5/-5 until end of turn. If that creature would die this turn, exile it instead.

Fledgling Djinn

Flying
At the beginning of your upkeep, Fledgling Djinn deals 1 damage to you.

Shepherd of Rot

{T}: Each player loses 1 life for each Zombie on the battlefield.

Gempalm Polluter

Cycling {B}{B} ({B}{B}, Discard this card: Draw a card.)
When you cycle Gempalm Polluter, you may have target player lose life equal to the number of Zombies on the battlefield.

Shamble Back

Exile target creature card from a graveyard. Create a 2/2 black Zombie creature token. You gain 2 life.

Thorn of the Black Rose

Deathtouch
When Thorn of the Black Rose enters, you become the monarch.

Dauthi Slayer

Shadow (This creature can block or be blocked by only creatures with shadow.)
Dauthi Slayer attacks each combat if able.

Sangrophage

At the beginning of your upkeep, tap Sangrophage unless you pay 2 life.

Shadowfeed

Exile target card from a graveyard. You gain 3 life.

Diabolic Edict

Target player sacrifices a creature of their choice.

Swamp

Dark Ritual

Dauthi Horror

Shadow (This creature can block or be blocked by only creatures with shadow.)
Dauthi Horror can't be blocked by white creatures.