Theater of Horrors

At the beginning of your upkeep, exile the top card of your library.
During your turn, if an opponent lost life this turn, you may play lands and cast spells from among cards exiled with Theater of Horrors.
{3}{R}: Theater of Horrors deals 1 damage to target opponent or planeswalker.

Curse of Chaos

Enchant player
Whenever a player attacks enchanted player with one or more creatures, that attacking player may discard a card. If the player does, they draw a card.

Bronze Bombshell

When a player other than Bronze Bombshell's owner controls it, that player sacrifices it. If the player does, Bronze Bombshell deals 7 damage to the player.

Harmless Offering

Target opponent gains control of target permanent you control.

Bloodchief Ascension

At the beginning of each end step, if an opponent lost 2 or more life this turn, you may put a quest counter on Bloodchief Ascension. (Damage causes loss of life.)
Whenever a card is put into an opponent's graveyard from anywhere, if Bloodchief Ascension has three or more quest counters on it, you may have that player lose 2 life. If you do, you gain 2 life.

Luxury Suite

Luxury Suite enters the battlefield tapped unless you have two or more opponents.
{T}: Add {B} or {R}.

Phyrexian Etchings

Cumulative upkeep {B} (At the beginning of your upkeep, put an age counter on this permanent, then sacrifice it unless you pay its upkeep cost for each age counter on it.)
At the beginning of your end step, draw a card for each age counter on Phyrexian Etchings.
When Phyrexian Etchings is put into a graveyard from the battlefield, you lose 2 life for each age counter on it.

Bazaar Trader

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

Victory Chimes

Untap Victory Chimes during each other player's untap step.
{T}: A player of your choice adds {C}.

Pyxis of Pandemonium

{T}: Each player exiles the top card of their library face down.
{7}, {T}, Sacrifice Pyxis of Pandemonium: Each player turns face up all cards they own exiled with Pyxis of Pandemonium, then puts all permanent cards among them onto the battlefield.

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.

Confusion in the Ranks

Whenever an artifact, creature, or enchantment enters the battlefield, its controller chooses target permanent another player controls that shares a card type with it. Exchange control of those permanents.

Pendant of Prosperity

Pendant of Prosperity enters the battlefield 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.

Goblin Game

Each player hides at least one item, then all players reveal them simultaneously. Each player loses life equal to the number of items they revealed. The player who revealed the fewest items then loses half their life, rounded up. If two or more players are tied for fewest, each loses half their life, rounded up.

Warp World

Each player shuffles all permanents they own into their library, then reveals that many cards from the top of their library. Each player puts all artifact, creature, and land cards revealed this way onto the battlefield, then does the same for enchantment cards, then puts all cards revealed this way that weren't put onto the battlefield on the bottom of their library.

Hissing Miasma

Whenever a creature attacks you, its controller loses 1 life.

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.

Indomitable Creativity

Destroy X target artifacts and/or creatures. For each permanent destroyed this way, its controller reveals cards from the top of their library until an artifact or creature card is revealed and exiles that card. Those players put the exiled cards onto the battlefield, then shuffle.

Torment of Scarabs

Enchant player
At the beginning of enchanted player's upkeep, that player loses 3 life unless they sacrifice a nonland permanent or discard a card.

Tide of War

Whenever one or more creatures block, flip a coin. If you win the flip, each blocking creature is sacrificed by its controller. If you lose the flip, each blocked creature is sacrificed by its controller.

Curse of the Nightly Hunt

Enchant player
Creatures enchanted player controls attack each combat if able.

Havoc Festival

Players can't gain life.
At the beginning of each player's upkeep, that player loses half their life, rounded up.

Furnace of Rath

If a source would deal damage to a permanent or player, it deals double that damage to that permanent or player instead.

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.")

Aggressive Mining

You can't play lands.
Sacrifice a land: Draw two cards. Activate only once each turn.

Curse of Vengeance

Enchant player
Whenever enchanted player casts a spell, put a spite counter on Curse of Vengeance.
When enchanted player loses the game, you gain X life and draw X cards, where X is the number of spite counters on Curse of Vengeance.

Vow of Lightning

Enchant creature
Enchanted creature gets +2/+2, has first strike, and can't attack you or planeswalkers you control.

Blood Crypt

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

Marchesa's Decree

When Marchesa's Decree enters the battlefield, you become the monarch.
Whenever a creature attacks you or a planeswalker you control, that creature's controller loses 1 life.

Blood Reckoning

Whenever a creature attacks you or a planeswalker you control, that creature's controller loses 1 life.

Heartstone

Activated abilities of creatures cost {1} less to activate. This effect can't reduce the mana in that cost to less than one mana.

Rite of the Raging Storm

Creatures named Lightning Rager can't attack you or planeswalkers you control.
At the beginning of each player's upkeep, that player creates a 5/1 red Elemental creature token named Lightning Rager. It has trample, haste, and "At the beginning of the end step, sacrifice this creature."

Dragonskull Summit

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

Captive Audience

Captive Audience enters the battlefield under the control of an opponent of your choice.
At the beginning of your upkeep, choose one that hasn't been chosen —
• Your life total becomes 4.
• Discard your hand.
• Each opponent creates five 2/2 black Zombie creature tokens.

Sower of Discord

Flying
As Sower of Discord enters the battlefield, choose two players.
Whenever damage is dealt to one of the chosen players, the other chosen player also loses that much life.

Sulfurous Springs

{T}: Add {C}.
{T}: Add {B} or {R}. Sulfurous Springs deals 1 damage to you.

Foreboding Ruins

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

Thran Turbine

At the beginning of your upkeep, you may add {C}{C}. You can't spend this mana to cast spells.

Risky Move

At the beginning of each player's upkeep, that player gains control of Risky Move.
When you gain control of Risky Move from another player, choose a creature you control and an opponent. Flip a coin. If you lose the flip, that opponent gains control of that creature.

Scheming Symmetry

Choose two target players. Each of them searches their library for a card, then shuffles and puts that card on top.

Possibility Storm

Whenever a player casts a spell from their hand, that player exiles it, then exiles cards from the top of their library until they exile a card that shares a card type with it. That player may cast that card without paying its mana cost. Then they put all cards exiled with Possibility Storm on the bottom of their library in a random order.

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.

Bitter Feud

As Bitter Feud enters the battlefield, choose two players.
If a source controlled by one of the chosen players would deal damage to the other chosen player or a permanent that player controls, that source deals double that damage to that player or permanent instead.

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.

Grid Monitor

Curse of Thirst

Enchant player
At the beginning of enchanted player's upkeep, Curse of Thirst deals damage to that player equal to the number of Curses attached to them.

Curse of Death's Hold

Enchant player
Creatures enchanted player controls get -1/-1.

Dictate of the Twin Gods

Flash
If a source would deal damage to a permanent or player, it deals double that damage to that permanent or player instead.

Curse of Bloodletting

Enchant player
If a source would deal damage to enchanted player, it deals double that damage to that player instead.

Curse of Stalked Prey

Enchant player
Whenever a creature deals combat damage to enchanted player, put a +1/+1 counter on that creature.

Trespasser's Curse

Enchant player
Whenever a creature enters the battlefield under enchanted player's control, that player loses 1 life and you gain 1 life.

Cruel Reality

Enchant player
At the beginning of enchanted player's upkeep, that player sacrifices a creature or planeswalker. If the player can't, they lose 5 life.

Kazuul, Tyrant of the Cliffs

Whenever a creature an opponent controls attacks, if you're the defending player, create a 3/3 red Ogre creature token unless that creature's controller pays {3}.

Temple of Malice

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

Bitterheart Witch

Deathtouch
When Bitterheart Witch dies, you may search your library for a Curse card, put it onto the battlefield attached to target player, then shuffle.

Phyrexian Negator

Trample
Whenever Phyrexian Negator is dealt damage, sacrifice that many permanents.

Curse of Shallow Graves

Enchant player
Whenever a player attacks enchanted player with one or more creatures, that attacking player may create a tapped 2/2 black Zombie creature token.

Vow of Malice

Enchant creature
Enchanted creature gets +2/+2, has intimidate, and can't attack you or planeswalkers you control. (A creature with intimidate can't be blocked except by artifact creatures and/or creatures that share a color with it.)

Xantcha, Sleeper Agent

Xantcha, Sleeper Agent enters the battlefield 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.

Varchild, Betrayer of Kjeldor

Whenever Varchild, Betrayer of Kjeldor deals combat damage to a player, that player creates that many 1/1 red Survivor creature tokens.
Survivors your opponents control can't block, and they can't attack you or planeswalkers you control.
When Varchild leaves the battlefield, gain control of all Survivors.

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.

Akroan Horse

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

Curse of Misfortunes

Enchant player
At the beginning of your upkeep, you may search your library for a Curse card that doesn't have the same name as a Curse attached to enchanted player, put it onto the battlefield attached to that player, then shuffle.

Bloodthirsty Blade

Equipped creature gets +2/+0 and is goaded. (It attacks each combat if able and attacks a player other than you if able.)
{1}: Attach Bloodthirsty Blade to target creature an opponent controls. Activate only as a sorcery.

Demonic Pact

At the beginning of your upkeep, choose one that hasn't been chosen —
• Demonic Pact deals 4 damage to any target and you gain 4 life.
• Target opponent discards two cards.
• Draw two cards.
• You lose the game.

Bloodstained Mire

{T}, Pay 1 life, Sacrifice Bloodstained Mire: Search your library for a Swamp or Mountain card, put it onto the battlefield, then shuffle.

Curse of Disturbance

Enchant player
Whenever enchanted player is attacked, create a 2/2 black Zombie creature token. Each opponent attacking that player does the same.

Steel Golem

Smoldering Marsh

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

Thieves' Auction

Exile all nontoken permanents. Starting with you, each player chooses one of the exiled cards and puts it onto the battlefield tapped under their control. Repeat this process until all cards exiled this way have been chosen.

Krark's Thumb

If you would flip a coin, instead flip two coins and ignore one.

War's Toll

Whenever an opponent taps a land for mana, tap all lands that player controls.
If a creature an opponent controls attacks, all creatures that opponent controls attack if able.