Cabal Coffers

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

Death Baron

Skeletons you control and other Zombies you control get +1/+1 and have deathtouch. (Any amount of damage they deal to a creature is enough to destroy it.)

Gutterbones

This creature enters tapped.
{1}{B}: Return this card from your graveyard to your hand. Activate only during your turn and only if an opponent lost life this turn.

High Market

{T}: Add {C}.
{T}, Sacrifice a creature: You gain 1 life.

Swamp

Myriad Landscape

This land enters tapped.
{T}: Add {C}.
{2}, {T}, Sacrifice this land: Search your library for up to two basic land cards that share a land type, put them onto the battlefield tapped, then shuffle.

Ozox, the Clattering King

Ozox can't block.
When Ozox dies, create Jumblebones, a legendary 2/1 black Skeleton creature token with "Jumblebones can't block" and "When Jumblebones leaves the battlefield, return target card named Ozox, the Clattering King from your graveyard to your hand."

Arcane Signet

{T}: Add one mana of any color in your commander's color identity.

Carrion Feeder

This creature can't block.
Sacrifice a creature: Put a +1/+1 counter on this creature.

Cabal Stronghold

{T}: Add {C}.
{3}, {T}: Add {B} for each basic Swamp you control.

Wayfarer's Bauble

{2}, {T}, Sacrifice this artifact: Search your library for a basic land card, put that card onto the battlefield tapped, then shuffle.

Urborg, Tomb of Yawgmoth

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

Desecrated Tomb

Whenever one or more creature cards leave your graveyard, create a 1/1 black Bat creature token with flying.

Charcoal Diamond

This artifact enters tapped.
{T}: Add {B}.

Persistent Specimen

{2}{B}: Return this card from your graveyard to the battlefield tapped.

Ashnod's Altar

Spymaster's Vault

This land enters tapped unless you control a Swamp.
{T}: Add {B}.
{B}, {T}: Target creature you control connives X, where X is the number of creatures that died this turn. (Draw X cards, then discard X cards. Put a +1/+1 counter on that creature for each nonland card discarded this way.)

Relic of Legends

{T}: Add one mana of any color.
Tap an untapped legendary creature you control: Add one mana of any color.

Jet Medallion

Black spells you cast cost {1} less to cast.

Grave Pact

Whenever a creature you control dies, each other player sacrifices a creature of their choice.

Skeleton Crew

Each other creature you control that's a Skeleton or Pirate gets +1/+1.
Whenever one or more creature cards leave your graveyard, create a 2/2 black Skeleton Pirate creature token. (This ability triggers only from the battlefield.)
{5}{B}: Return this card from your graveyard to the battlefield tapped.

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.)

Sol Ring

Death-Priest of Myrkul

Skeletons, Vampires, and Zombies you control get +1/+1.
At the beginning of your end step, if a creature died this turn, you may pay {1}. If you do, create a 1/1 black Skeleton creature token.

Blood Artist

Whenever this creature or another creature dies, target player loses 1 life and you gain 1 life.

Thought Vessel

You have no maximum hand size.
{T}: Add {C}.

Accursed Marauder

When this creature enters, each player sacrifices a nontoken creature of their choice.

Swiftfoot Boots

Equipped creature has hexproof and haste. (It can't be the target of spells or abilities your opponents control. It can attack and {T} no matter when it came under your control.)
Equip {1} ({1}: Attach to target creature you control. Equip only as a sorcery.)

Zulaport Cutthroat

Whenever this creature or another creature you control dies, each opponent loses 1 life and you gain 1 life.

Bojuka Bog

This land enters tapped.
When this land enters, exile target player's graveyard.
{T}: Add {B}.

Ayara, First of Locthwain

Whenever Ayara or another black creature you control enters, each opponent loses 1 life and you gain 1 life.
{T}, Sacrifice another black creature: Draw a card.