Chainer, Dementia Master

All Nightmares get +1/+1.
{B}{B}{B}, Pay 3 life: Put target creature card from a graveyard onto the battlefield under your control. That creature is black and is a Nightmare in addition to its other creature types.
When Chainer, Dementia Master leaves the battlefield, exile all Nightmares.

Blighted Fen

{T}: Add {C}.
{4}{B}, {T}, Sacrifice Blighted Fen: Target opponent sacrifices a creature.

Deathgreeter

Whenever another creature dies, you may gain 1 life.

Aetherflux Reservoir

Whenever you cast a spell, you gain 1 life for each spell you've cast this turn.
Pay 50 life: Aetherflux Reservoir deals 50 damage to any target.

Caged Sun

As Caged Sun enters the battlefield, choose a color.
Creatures you control of the chosen color get +1/+1.
Whenever a land's ability causes you to add one or more mana of the chosen color, add one additional mana of that color.

Nirkana Revenant

Whenever you tap a Swamp for mana, add an additional {B}.
{B}: Nirkana Revenant gets +1/+1 until end of turn.

Haunted Fengraf

{T}: Add {C}.
{3}, {T}, Sacrifice Haunted Fengraf: Return a creature card at random from your graveyard to your hand.

Rogue's Passage

{T}: Add {C}.
{4}, {T}: Target creature can't be blocked this turn.

Cloak and Dagger

Equipped creature gets +2/+0 and has shroud. (It can't be the target of spells or abilities.)
Whenever a Rogue creature enters the battlefield, you may attach Cloak and Dagger to it.
Equip {3}

Pawn of Ulamog

Whenever Pawn of Ulamog or another nontoken creature you control dies, you may create a 0/1 colorless Eldrazi Spawn creature token. It has "Sacrifice this creature: Add {C}."

Mage-Ring Network

{T}: Add {C}.
{1}, {T}: Put a storage counter on Mage-Ring Network.
{T}, Remove any number of storage counters from Mage-Ring Network: Add {C} for each storage counter removed this way.

Midnight Banshee

Wither (This deals damage to creatures in the form of -1/-1 counters.)
At the beginning of your upkeep, put a -1/-1 counter on each nonblack creature.

Butcher Ghoul

Undying (When this creature dies, if it had no +1/+1 counters on it, return it to the battlefield under its owner's control with a +1/+1 counter on it.)

Swamp

Thespian's Stage

{T}: Add {C}.
{2}, {T}: Thespian's Stage becomes a copy of target land, except it has this ability.

Ob Nixilis, Unshackled

Flying, trample
Whenever an opponent searches their library, that player sacrifices a creature and loses 10 life.
Whenever another creature dies, put a +1/+1 counter on Ob Nixilis, Unshackled.

Phyrexian Altar

Sacrifice a creature: Add one mana of any color.

Ichor Rats

Infect (This creature deals damage to creatures in the form of -1/-1 counters and to players in the form of poison counters.)
When Ichor Rats enters the battlefield, each player gets a poison counter.

Myriad Landscape

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

Massacre Girl

Menace
When Massacre Girl enters the battlefield, each other creature gets -1/-1 until end of turn. Whenever a creature dies this turn, each creature other than Massacre Girl gets -1/-1 until end of turn.

Whispersilk Cloak

Equipped creature can't be blocked and has shroud. (It can't be the target of spells or abilities.)
Equip {2}

Hangarback Walker

Hangarback Walker enters the battlefield with X +1/+1 counters on it.
When Hangarback Walker dies, create a 1/1 colorless Thopter artifact creature token with flying for each +1/+1 counter on Hangarback Walker.
{1}, {T}: Put a +1/+1 counter on Hangarback Walker.

Massacre Wurm

When Massacre Wurm enters the battlefield, creatures your opponents control get -2/-2 until end of turn.
Whenever a creature an opponent controls dies, that player loses 2 life.

Nim Deathmantle

Equipped creature gets +2/+2, has intimidate, and is a black Zombie. (A creature with intimidate can't be blocked except by artifact creatures and/or creatures that share a color with it.)
Whenever a nontoken creature is put into your graveyard from the battlefield, you may pay {4}. If you do, return that card to the battlefield and attach Nim Deathmantle to it.
Equip {4}

Demonic Tutor

Search your library for a card, put that card into your hand, then shuffle.

Expedition Map

{2}, {T}, Sacrifice Expedition Map: Search your library for a land card, reveal it, put it into your hand, then shuffle.

Damnation

Destroy all creatures. They can't be regenerated.

Darkness

Prevent all combat damage that would be dealt this turn.

Decree of Pain

Destroy all creatures. They can't be regenerated. Draw a card for each creature destroyed this way.
Cycling {3}{B}{B} ({3}{B}{B}, Discard this card: Draw a card.)
When you cycle Decree of Pain, all creatures get -2/-2 until end of turn.

Endrek Sahr, Master Breeder

Whenever you cast a creature spell, create X 1/1 black Thrull creature tokens, where X is that spell's mana value.
When you control seven or more Thrulls, sacrifice Endrek Sahr, Master Breeder.

Gray Merchant of Asphodel

When Gray Merchant of Asphodel enters the battlefield, 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.)

Cabal Coffers

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

Nest of Scarabs

Whenever you put one or more -1/-1 counters on a creature, create that many 1/1 black Insect creature tokens.

Darksteel Reactor

Indestructible (Effects that say "destroy" don't destroy this artifact.)
At the beginning of your upkeep, you may put a charge counter on Darksteel Reactor.
When Darksteel Reactor has twenty or more charge counters on it, you win the game.

Phyresis

Enchant creature
Enchanted creature has infect. (It deals damage to creatures in the form of -1/-1 counters and to players in the form of poison counters.)

Commander's Sphere

{T}: Add one mana of any color in your commander's color identity.
Sacrifice Commander's Sphere: Draw a card.

Revel in Riches

Whenever a creature an opponent controls dies, create a Treasure token. (It's an artifact with "{T}, Sacrifice this artifact: Add one mana of any color.")
At the beginning of your upkeep, if you control ten or more Treasures, you win the game.

Crypt of Agadeem

Crypt of Agadeem enters the battlefield tapped.
{T}: Add {B}.
{2}, {T}: Add {B} for each black creature card in your graveyard.

Crumbling Ashes

At the beginning of your upkeep, destroy target creature with a -1/-1 counter on it.

Crypt Ghast

Extort (Whenever you cast a spell, you may pay {W/B}. If you do, each opponent loses 1 life and you gain that much life.)
Whenever you tap a Swamp for mana, add an additional {B}.

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.)

Glistening Oil

Enchant creature
Enchanted creature has infect.
At the beginning of your upkeep, put a -1/-1 counter on enchanted creature.
When Glistening Oil is put into a graveyard from the battlefield, return Glistening Oil to its owner's hand.

Swiftfoot Boots

Equipped creature has hexproof and haste. (It can't be the target of spells or abilities your opponents control.)
Equip {1}

Desert of the Glorified

Desert of the Glorified enters the battlefield tapped.
{T}: Add {B}.
Cycling {1}{B} ({1}{B}, Discard this card: Draw a card.)

Karn's Bastion

{T}: Add {C}.
{4}, {T}: Proliferate. (Choose any number of permanents and/or players, then give each another counter of each kind already there.)

Living Death

Each player exiles all creature cards from their graveyard, then sacrifices all creatures they control, then puts all cards they exiled this way onto the battlefield.

Toxic Deluge

As an additional cost to cast this spell, pay X life.
All creatures get -X/-X until end of turn.

Gilded Lotus

Sol Ring

Necroskitter

Wither (This deals damage to creatures in the form of -1/-1 counters.)
Whenever a creature an opponent controls with a -1/-1 counter on it dies, you may return that card to the battlefield under your control.

Solemn Simulacrum

When Solemn Simulacrum enters the battlefield, you may search your library for a basic land card, put that card onto the battlefield tapped, then shuffle.
When Solemn Simulacrum dies, you may draw a card.

Hand of the Praetors

Infect (This creature deals damage to creatures in the form of -1/-1 counters and to players in the form of poison counters.)
Other creatures you control with infect get +1/+1.
Whenever you cast a creature spell with infect, target player gets a poison counter.

Skithiryx, the Blight Dragon

Flying
Infect (This creature deals damage to creatures in the form of -1/-1 counters and to players in the form of poison counters.)
{B}: Skithiryx, the Blight Dragon gains haste until end of turn.
{B}{B}: Regenerate Skithiryx.

Ashnod's Altar

Bontu's Monument

Black creature spells you cast cost {1} less to cast.
Whenever you cast a creature spell, each opponent loses 1 life and you gain 1 life.

Bolas's Citadel

You may look at the top card of your library any time.
You may play lands and cast spells from the top of your library. If you cast a spell this way, pay life equal to its mana value rather than pay its mana cost.
{T}, Sacrifice ten nonland permanents: Each opponent loses 10 life.

Core Prowler

Infect (This creature deals damage to creatures in the form of -1/-1 counters and to players in the form of poison counters.)
When Core Prowler dies, proliferate. (Choose any number of permanents and/or players, then give each another counter of each kind already there.)

Faith of the Devoted

Whenever you cycle or discard a card, you may pay {1}. If you do, each opponent loses 2 life and you gain 2 life.

Cauldron of Souls

{T}: Choose any number of target creatures. Each of those creatures gains persist until end of turn. (When it dies, if it had no -1/-1 counters on it, return it to the battlefield under its owner's control with a -1/-1 counter on it.)

Geralf's Messenger

Geralf's Messenger enters the battlefield tapped.
When Geralf's Messenger enters the battlefield, target opponent loses 2 life.
Undying (When this creature dies, if it had no +1/+1 counters on it, return it to the battlefield under its owner's control with a +1/+1 counter on it.)

Bojuka Bog

Bojuka Bog enters the battlefield tapped.
When Bojuka Bog enters the battlefield, exile target player's graveyard.
{T}: Add {B}.

Urborg, Tomb of Yawgmoth

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

Phyrexian Arena

At the beginning of your upkeep, you draw a card and you lose 1 life.

All Is Dust

Each player sacrifices all permanents they control that are one or more colors.

Tortured Existence

{B}, Discard a creature card: Return target creature card from your graveyard to your hand.

Memorial to Folly

Memorial to Folly enters the battlefield tapped.
{T}: Add {B}.
{2}{B}, {T}, Sacrifice Memorial to Folly: Return target creature card from your graveyard to your hand.

Puppeteer Clique

Flying
When Puppeteer Clique enters the battlefield, put target creature card from an opponent's graveyard onto the battlefield under your control. It gains haste. At the beginning of your next end step, exile it.
Persist (When this creature dies, if it had no -1/-1 counters on it, return it to the battlefield under its owner's control with a -1/-1 counter on it.)

Black Sun's Zenith

Put X -1/-1 counters on each creature. Shuffle Black Sun's Zenith into its owner's library.

Barren Moor

Barren Moor enters the battlefield tapped.
{T}: Add {B}.
Cycling {B} ({B}, Discard this card: Draw a card.)

Torment of Hailfire

Repeat the following process X times. Each opponent loses 3 life unless that player sacrifices a nonland permanent or discards a card.

Necroplasm

At the beginning of your upkeep, put a +1/+1 counter on Necroplasm.
At the beginning of your end step, destroy each creature with mana value equal to the number of +1/+1 counters on Necroplasm.
Dredge 2 (If you would draw a card, you may mill two cards instead. If you do, return this card from your graveyard to your hand.)

Sengir Autocrat

When Sengir Autocrat enters the battlefield, create three 0/1 black Serf creature tokens.
When Sengir Autocrat leaves the battlefield, exile all Serf tokens.

Abhorrent Overlord

Flying
When Abhorrent Overlord enters the battlefield, create a number of 1/1 black Harpy creature tokens with flying equal to your devotion to black. (Each {B} in the mana costs of permanents you control counts toward your devotion to black.)
At the beginning of your upkeep, sacrifice a creature.

Mortuary Mire

Mortuary Mire enters the battlefield tapped.
When Mortuary Mire enters the battlefield, you may put target creature card from your graveyard on top of your library.
{T}: Add {B}.

Sheoldred, Whispering One

Swampwalk (This creature can't be blocked as long as defending player controls a Swamp.)
At the beginning of your upkeep, return target creature card from your graveyard to the battlefield.
At the beginning of each opponent's upkeep, that player sacrifices a creature.

The Elderspell

Destroy any number of target planeswalkers. Choose a planeswalker you control. Put two loyalty counters on it for each planeswalker destroyed this way.

Arcane Lighthouse

{T}: Add {C}.
{1}, {T}: Until end of turn, creatures your opponents control lose hexproof and shroud and can't have hexproof or shroud.

Dance of the Dead

Enchant creature card in a graveyard
When Dance of the Dead enters the battlefield, if it's on the battlefield, it loses "enchant creature card in a graveyard" and gains "enchant creature put onto the battlefield with Dance of the Dead." Put enchanted creature card onto the battlefield tapped under your control and attach Dance of the Dead to it. When Dance of the Dead leaves the battlefield, that creature's controller sacrifices it.
Enchanted creature gets +1/+1 and doesn't untap during its controller's untap step.
At the beginning of the upkeep of enchanted creature's controller, that player may pay {1}{B}. If the player does, untap that creature.

Cabal Stronghold

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

Ophiomancer

At the beginning of each upkeep, if you control no Snakes, create a 1/1 black Snake creature token with deathtouch.

Imp's Mischief

Change the target of target spell with a single target. You lose life equal to that spell's mana value.

Diabolic Intent

As an additional cost to cast this spell, sacrifice a creature.
Search your library for a card, put that card into your hand, then shuffle.

Vivid Marsh

Vivid Marsh enters the battlefield tapped with two charge counters on it.
{T}: Add {B}.
{T}, Remove a charge counter from Vivid Marsh: Add one mana of any color.

Black Market

Whenever a creature dies, put a charge counter on Black Market.
At the beginning of your precombat main phase, add {B} for each charge counter on Black Market.