Xantcha, Sleeper Agent

Xantcha, Sleeper Agent enters under the control of an opponent of your choice.
Xantcha attacks each combat if able and can't attack its owner or planeswalkers its owner controls.
{3}: Xantcha's controller loses 2 life and you draw a card. Any player may activate this ability.

Foreboding Ruins

As Foreboding Ruins enters, you may reveal a Swamp or Mountain card from your hand. If you don't, Foreboding Ruins enters tapped.
{T}: Add {B} or {R}.

Temple of Malice

Temple of Malice enters tapped.
When Temple of Malice enters, scry 1.
{T}: Add {B} or {R}.

Strionic Resonator

{2}, {T}: Copy target triggered ability you control. You may choose new targets for the copy. (A triggered ability uses the words "when," "whenever," or "at.")

Rakdos Charm

Choose one —
• Exile target player's graveyard.
• Destroy target artifact.
• Each creature deals 1 damage to its controller.

Coldsteel Heart

Coldsteel Heart enters tapped.
As Coldsteel Heart enters, choose a color.
{T}: Add one mana of the chosen color.

Scourge of Numai

At the beginning of your upkeep, you lose 2 life if you don't control an Ogre.

Jinxed Choker

At the beginning of your end step, target opponent gains control of Jinxed Choker and puts a charge counter on it.
At the beginning of your upkeep, Jinxed Choker deals damage to you equal to the number of charge counters on it.
{3}: Put a charge counter on Jinxed Choker or remove one from it.

Humble Defector

{T}: Draw two cards. Target opponent gains control of Humble Defector. Activate only during your turn.

Lurking Jackals

When an opponent has 10 or less life, if Lurking Jackals is an enchantment, it becomes a 3/2 Jackal creature.

Lord of the Pit

Flying, trample
At the beginning of your upkeep, sacrifice a creature other than Lord of the Pit. If you can't, Lord of the Pit deals 7 damage to you.

Chaos Warp

The owner of target permanent shuffles it into their library, then reveals the top card of their library. If it's a permanent card, they put it onto the battlefield.

Rakdos Signet

Brand

Gain control of all permanents you own. (This effect lasts indefinitely.)
Cycling {2} ({2}, Discard this card: Draw a card.)

Goblin War Wagon

Goblin War Wagon doesn't untap during your untap step.
At the beginning of your upkeep, you may pay {2}. If you do, untap Goblin War Wagon.

Mountain

Geth's Grimoire

Whenever an opponent discards a card, you may draw a card.

Font of Mythos

At the beginning of each player's draw step, that player draws two additional cards.

Harmless Offering

Target opponent gains control of target permanent you control.

Canyon Slough

({T}: Add {B} or {R}.)
Canyon Slough enters tapped.
Cycling {2} ({2}, Discard this card: Draw a card.)

Blood Mist

At the beginning of combat on your turn, target creature you control gains double strike until end of turn.

Andradite Leech

Black spells you cast cost {B} more to cast.
{B}: Andradite Leech gets +1/+1 until end of turn.

Akroan Horse

Defender
When Akroan Horse enters, an opponent gains control of it.
At the beginning of your upkeep, each opponent creates a 1/1 white Soldier creature token.

Megrim

Whenever an opponent discards a card, Megrim deals 2 damage to that player.

Arcane Signet

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

Loafing Giant

Whenever Loafing Giant attacks or blocks, mill a card. If a land card was milled this way, prevent all combat damage Loafing Giant would deal this turn.

Waste Not

Whenever an opponent discards a creature card, create a 2/2 black Zombie creature token.
Whenever an opponent discards a land card, add {B}{B}.
Whenever an opponent discards a noncreature, nonland card, draw a card.

Liege of the Pit

Flying, trample
At the beginning of your upkeep, sacrifice a creature other than Liege of the Pit. If you can't, Liege of the Pit deals 7 damage to you.
Morph {B}{B}{B}{B} (You may cast this card face down as a 2/2 creature for {3}. Turn it face up any time for its morph cost.)

Mind Stone

{T}: Add {C}.
{1}, {T}, Sacrifice Mind Stone: Draw a card.

Smoldering Marsh

({T}: Add {B} or {R}.)
Smoldering Marsh enters tapped unless you control two or more basic lands.

Crown of Doom

Whenever a creature attacks you or a planeswalker you control, it gets +2/+0 until end of turn.
{2}: Target player other than Crown of Doom's owner gains control of it. Activate only during your turn.

Cinder Giant

At the beginning of your upkeep, Cinder Giant deals 2 damage to each other creature you control.

Blood Crypt

({T}: Add {B} or {R}.)
As Blood Crypt enters, you may pay 2 life. If you don't, it enters tapped.

Abyssal Persecutor

Flying, trample
You can't win the game and your opponents can't lose the game.

Ogre Recluse

Whenever a player casts a spell, tap Ogre Recluse.

Qal Sisma Behemoth

Qal Sisma Behemoth can't attack or block unless you pay {2}.

Vandalblast

Destroy target artifact you don't control.
Overload {4}{R} (You may cast this spell for its overload cost. If you do, change "target" in its text to "each.")

Blim, Comedic Genius

Flying
Whenever Blim, Comedic Genius deals combat damage to a player, that player gains control of target permanent you control. Then each player loses life and discards cards equal to the number of permanents they control but don't own.

Fire Diamond

Fire Diamond enters tapped.
{T}: Add {R}.

Fellwar Stone

{T}: Add one mana of any color that a land an opponent controls could produce.

Orcish Conscripts

Orcish Conscripts can't attack unless at least two other creatures attack.
Orcish Conscripts can't block unless at least two other creatures block.

Darksteel Relic

Indestructible (Effects that say "destroy" don't destroy this artifact.)

Ebon Drake

Flying
Whenever a player casts a spell, you lose 1 life.

Rakdos's Return

Rakdos's Return deals X damage to target opponent or planeswalker. That player or that planeswalker's controller discards X cards.

Sol Ring

Rust Elemental

Flying
At the beginning of your upkeep, sacrifice an artifact other than Rust Elemental. If you can't, tap Rust Elemental and you lose 4 life.

Dragonskull Summit

Dragonskull Summit enters tapped unless you control a Swamp or a Mountain.
{T}: Add {B} or {R}.

Bojuka Bog

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

Wirecat

Wirecat can't attack or block if an enchantment is on the battlefield.

Whispersilk Cloak

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

Jinxed Idol

At the beginning of your upkeep, Jinxed Idol deals 2 damage to you.
Sacrifice a creature: Target opponent gains control of Jinxed Idol.

Branded Brawlers

Branded Brawlers can't attack if defending player controls an untapped land.
Branded Brawlers can't block if you control an untapped land.

Bazaar Trader

{T}: Target player gains control of target artifact, creature, or land you control.

Commander's Sphere

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

Talisman of Indulgence

{T}: Add {C}.
{T}: Add {B} or {R}. Talisman of Indulgence deals 1 damage to you.

Ghostly Flame

Black and/or red permanents and spells are colorless sources of damage.

Tinybones, Trinket Thief

At the beginning of each end step, if an opponent discarded a card this turn, you draw a card and you lose 1 life.
{4}{B}{B}: Each opponent with no cards in hand loses 10 life.

Swamp

Homeward Path

{T}: Add {C}.
{T}: Each player gains control of all creatures they own.

Charcoal Diamond

Charcoal Diamond enters tapped.
{T}: Add {B}.

Bedevil

Destroy target artifact, creature, or planeswalker.

Steel Golem

Curse of Opulence

Enchant player
Whenever enchanted player is attacked, create a Gold token. Each opponent attacking that player does the same. (A Gold token is an artifact with "Sacrifice this artifact: Add one mana of any color.")

Goldnight Castigator

Flying, haste
If a source would deal damage to you, it deals double that damage to you instead.
If a source would deal damage to Goldnight Castigator, it deals double that damage to Goldnight Castigator instead.

Treacherous Pit-Dweller

When Treacherous Pit-Dweller enters from a graveyard, target opponent gains control of it.
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.)

Leechridden Swamp

({T}: Add {B}.)
Leechridden Swamp enters tapped.
{B}, {T}: Each opponent loses 1 life. Activate only if you control two or more black permanents.

Witch Hunt

Players can't gain life.
At the beginning of your upkeep, Witch Hunt deals 4 damage to you.
At the beginning of your end step, target opponent chosen at random gains control of Witch Hunt.

Pendant of Prosperity

Pendant of Prosperity enters under the control of an opponent of your choice.
{2}, {T}: Draw a card, then you may put a land card from your hand onto the battlefield. Pendant of Prosperity's owner draws a card, then that player may put a land card from their hand onto the battlefield.

Lightning Greaves

Equipped creature has haste and shroud. (It can't be the target of spells or abilities.)
Equip {0}

Dreadbore

Grid Monitor

Plague Reaver

At the beginning of your end step, sacrifice each other creature you control.
Discard two cards, Sacrifice Plague Reaver: Choose target opponent. Return Plague Reaver to the battlefield under that player's control at the beginning of their next upkeep.

Liliana's Caress

Whenever an opponent discards a card, that player loses 2 life.

Jagged Poppet

Whenever Jagged Poppet is dealt damage, discard that many cards.
Hellbent — Whenever Jagged Poppet deals combat damage to a player, if you have no cards in hand, that player discards cards equal to the damage.

Akoum Refuge

Akoum Refuge enters tapped.
When Akoum Refuge enters, you gain 1 life.
{T}: Add {B} or {R}.

Sleeper Agent

When Sleeper Agent enters, target opponent gains control of it.
At the beginning of your upkeep, Sleeper Agent deals 2 damage to you.