Consume Spirit

Spend only black mana on X.
Consume Spirit deals X damage to any target and you gain X life.

Urborg, Tomb of Yawgmoth

Each land is a Swamp in addition to its other land types.

Carnophage

At the beginning of your upkeep, tap Carnophage unless you pay 1 life.

Nykthos, Shrine to Nyx

{T}: Add {C}.
{2}, {T}: Choose a color. Add an amount of mana of that color equal to your devotion to that color. (Your devotion to a color is the number of mana symbols of that color in the mana costs of permanents you control.)

Cabal Coffers

{2}, {T}: Add {B} for each Swamp you control.

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.)

Sangrophage

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

Cuombajj Witches

{T}: Cuombajj Witches deals 1 damage to any target and 1 damage to any target of an opponent's choice.

Liliana's Specter

Flying
When Liliana's Specter enters, each opponent discards a card.

Highway Robber

When Highway Robber enters, target opponent loses 2 life and you gain 2 life.

Blood Fountain

When Blood Fountain enters, create a Blood token. (It's an artifact with "{1}, {T}, Discard a card, Sacrifice this artifact: Draw a card.")
{3}{B}, {T}, Sacrifice Blood Fountain: Return up to two target creature cards from your graveyard to your hand.

Necrosavant

{3}{B}{B}, Sacrifice a creature: Return Necrosavant from your graveyard to the battlefield. Activate only during your upkeep.

Drain Life

Spend only black mana on X.
Drain Life deals X damage to any target. You gain life equal to the damage dealt, but not more life than the player's life total before the damage was dealt, the planeswalker's loyalty before the damage was dealt, or the creature's toughness.