Toxic Deluge

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

Forgeborn Oreads

Constellation — Whenever Forgeborn Oreads or another enchantment you control enters, Forgeborn Oreads deals 1 damage to any target.

Arcane Signet

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

Grand Architect

Other blue creatures you control get +1/+1.
{U}: Target artifact creature becomes blue until end of turn.
Tap an untapped blue creature you control: Add {C}{C}. Spend this mana only to cast artifact spells or activate abilities of artifacts.

Swamp

Skull of Orm

{5}, {T}: Return target enchantment card from your graveyard to your hand.

Opposition Agent

Flash
You control your opponents while they're searching their libraries.
While an opponent is searching their library, they exile each card they find. You may play those cards for as long as they remain exiled, and you may spend mana as though it were mana of any color to cast them.

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.

Mountain

Curse of Surveillance

Enchant player
At the beginning of enchanted player's upkeep, any number of target players other than that player each draw cards equal to the number of Curses attached to that player.

Claws of Gix

{1}, Sacrifice a permanent: You gain 1 life.

Island

Phyrexian Arena

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

Infectious Curse

Enchant player
Spells you cast that target enchanted player cost {1} less to cast.
At the beginning of enchanted player's upkeep, that player loses 1 life and you gain 1 life.

Accursed Witch

Spells your opponents cast that target Accursed Witch cost {1} less to cast.
When Accursed Witch dies, return it to the battlefield transformed under your control attached to target opponent.

Accursed Witch // Infectious Curse

Geyadrone Dihada

Protection from permanents with corruption counters on them
+1: Each opponent loses 2 life and you gain 2 life. Put a corruption counter on up to one other target creature or planeswalker.
−3: Gain control of target creature or planeswalker until end of turn. Untap it and put a corruption counter on it. It gains haste until end of turn.
−7: Gain control of each permanent with a corruption counter on it.

Curse of the Pierced Heart

Enchant player
At the beginning of enchanted player's upkeep, Curse of the Pierced Heart deals 1 damage to that player or a planeswalker that player controls.

Commander's Sphere

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

Terminate

Destroy target creature. It can't be regenerated.

Curse of the Restless Dead

Enchant player
Whenever a land enchanted player controls enters, you create a 2/2 black Zombie creature token with decayed. (It can't block. When it attacks, sacrifice it at end of combat.)

Have

Fog Bank

Defender (This creature can't attack.)
Flying
Prevent all combat damage that would be dealt to and dealt by this creature.

Curse of Fool's Wisdom

Enchant player
Whenever enchanted player draws a card, they lose 2 life and you gain 2 life.
Madness {3}{B} (If you discard this card, discard it into exile. When you do, cast it for its madness cost or put it into your graveyard.)

Roiling Terrain

Destroy target land, then Roiling Terrain deals damage to that land's controller equal to the number of land cards in that player's graveyard.

Alpine Moon

As Alpine Moon enters, choose a nonbasic land card name.
Lands your opponents control with the chosen name lose all land types and abilities, and they gain "{T}: Add one mana of any color."

Pili-Pala

Flying
{2}, {Q}: Add one mana of any color. ({Q} is the untap symbol.)

Propaganda

Creatures can't attack you unless their controller pays {2} for each creature they control that's attacking you.

Curse of Shaken Faith

Enchant player
Whenever enchanted player casts a spell other than the first spell they cast each turn or copies a spell, Curse of Shaken Faith deals 2 damage to them.

Brine Giant

This spell costs {1} less to cast for each enchantment you control.

Nightscape Familiar

Blue spells and red spells you cast cost {1} less to cast.
{1}{B}: Regenerate Nightscape Familiar.

Dimir Aqueduct

Dimir Aqueduct enters tapped.
When Dimir Aqueduct enters, return a land you control to its owner's hand.
{T}: Add {U}{B}.

Rewind

Counter target spell. Untap up to four lands.

Trespasser's Curse

Enchant player
Whenever a creature enchanted player controls enters, that player loses 1 life and you gain 1 life.

Arcane Denial

Counter target spell. Its controller may draw up to two cards at the beginning of the next turn's upkeep.
You draw a card at the beginning of the next turn's upkeep.

Melt Terrain

Destroy target land. Melt Terrain deals 2 damage to that land's controller.

Dreadbore

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.

Curse of Bloodletting

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

Jace, Wielder of Mysteries

If you would draw a card while your library has no cards in it, you win the game instead.
+1: Target player mills two cards. Draw a card.
−8: Draw seven cards. Then if your library has no cards in it, you win the game.

Curse of Echoes

Enchant player
Whenever enchanted player casts an instant or sorcery spell, each other player may copy that spell and may choose new targets for the copy they control.

Cruel Reality

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

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.")

Szat's Will

Choose one. If you control a commander as you cast this spell, you may choose both instead.
• Each opponent sacrifices a creature they control with the greatest power.
• Exile all opponents' graveyards, then create X 0/1 black Thrull creature tokens, where X is the greatest power among creature cards exiled this way.

Curse of Unbinding

Enchant player
At the beginning of enchanted player's upkeep, that player reveals cards from the top of their library until they reveal a creature card. Put that card onto the battlefield under your control. That player puts the rest of the revealed cards into their graveyard.

Vampiric Tutor

Search your library for a card, then shuffle and put that card on top. You lose 2 life.

Doomwake Giant

Constellation — Whenever Doomwake Giant or another enchantment you control enters, creatures your opponents control get -1/-1 until end of turn.

In Garruk's Wake

Destroy all creatures you don't control and all planeswalkers you don't control.

Torment of Scarabs

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

Leveler

When Leveler enters, exile all cards from your library.

Command Tower

Blightning

Blightning deals 3 damage to target player or planeswalker. That player or that planeswalker's controller discards two cards.

Curse of Obsession

Enchant player
At the beginning of enchanted player's draw step, that player draws two additional cards.
At the beginning of enchanted player's end step, that player discards their hand.

Mirrormade

You may have Mirrormade enter as a copy of any artifact or enchantment on the battlefield.

Sage of Mysteries

Constellation — Whenever an enchantment you control enters, target player mills two cards.

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.

Cancel

Thran Dynamo

Sire of Insanity

At the beginning of each end step, each player discards their hand.

Lynde, Cheerful Tormentor

Deathtouch
Whenever a Curse is put into your graveyard from the battlefield, return it to the battlefield attached to you at the beginning of the next end step.
At the beginning of your upkeep, you may attach a Curse attached to you to one of your opponents. If you do, draw two cards.

Protean Thaumaturge

Constellation — Whenever an enchantment you control enters, you may have Protean Thaumaturge become a copy of another target creature, except it has this ability.

Maddening Hex

Enchant player
Whenever enchanted player casts a noncreature spell, roll a d6. Maddening Hex deals damage to that player equal to the result. Then attach Maddening Hex to another one of your opponents chosen at random.

Perilous Research

Draw two cards, then sacrifice a permanent.

Paradox Haze

Enchant player
At the beginning of enchanted player's first upkeep each turn, that player gets an additional upkeep step after this step.

Bedevil

Destroy target artifact, creature, or planeswalker.

Thoughtrender Lamia

Constellation — Whenever Thoughtrender Lamia or another enchantment you control enters, each opponent discards a card.

Doom Blade

Curse of Wizardry

As Curse of Wizardry enters, choose a color.
Whenever a player casts a spell of the chosen color, that player loses 1 life.

Izzet Boilerworks

Izzet Boilerworks enters tapped.
When Izzet Boilerworks enters, return a land you control to its owner's hand.
{T}: Add {U}{R}.

Rakdos Charm

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

Captive Audience

Captive Audience enters 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.

Treasure Hunt

Reveal cards from the top of your library until you reveal a nonland card, then put all cards revealed this way into your hand.

Rakdos Carnarium

Rakdos Carnarium enters tapped.
When Rakdos Carnarium enters, return a land you control to its owner's hand.
{T}: Add {B}{R}.

Cloud Key

As Cloud Key enters, choose artifact, creature, enchantment, instant, or sorcery.
Spells you cast of the chosen type cost {1} less to cast.

Callaphe, Beloved of the Sea

Callaphe's power is equal to your devotion to blue. (Each {U} in the mana costs of permanents you control counts toward your devotion to blue.)
Creatures and enchantments you control have "Spells your opponents cast that target this permanent cost {1} more to cast."

Curse of Death's Hold

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

Sol Ring

Curse of Stalked Prey

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

Cleansing Wildfire

Destroy target land. Its controller may search their library for a basic land card, put it onto the battlefield tapped, then shuffle.
Draw a card.

Gitaxian Probe

({U/P} can be paid with either {U} or 2 life.)
Look at target player's hand.
Draw a card.

Laboratory Maniac

If you would draw a card while your library has no cards in it, you win the game instead.

Archfiend of Depravity

Flying
At the beginning of each opponent's end step, that player chooses up to two creatures they control, then sacrifices the rest.

Grim Guardian

Constellation — Whenever Grim Guardian or another enchantment you control enters, each opponent loses 1 life.

Thassa's Oracle

When Thassa's Oracle enters, look at the top X cards of your library, where X is your devotion to blue. Put up to one of them on top of your library and the rest on the bottom of your library in a random order. If X is greater than or equal to the number of cards in your library, you win the game. (Each {U} in the mana costs of permanents you control counts toward your devotion to blue.)

Winter Orb

As long as Winter Orb is untapped, players can't untap more than one land during their untap steps.

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.

Dreamshaper Shaman

At the beginning of your end step, you may pay {2}{R} and sacrifice a nonland permanent. If you do, reveal cards from the top of your library until you reveal a nonland permanent card. Put that card onto the battlefield and the rest on the bottom of your library in a random order.