Guilty Conscience

Enchant creature
Whenever enchanted creature deals damage, Guilty Conscience deals that much damage to that creature.

Mountain

Furycalm Snarl

As Furycalm Snarl enters, you may reveal a Mountain or Plains card from your hand. If you don't, Furycalm Snarl enters tapped.
{T}: Add {R} or {W}.

Sulfuric Vortex

At the beginning of each player's upkeep, Sulfuric Vortex deals 2 damage to that player.
If a player would gain life, that player gains no life instead.

Sunlit Marsh

({T}: Add {W} or {B}.)
Sunlit Marsh enters tapped.

Clifftop Retreat

Clifftop Retreat enters tapped unless you control a Mountain or a Plains.
{T}: Add {R} or {W}.

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.")

Oblivion Ring

When Oblivion Ring enters, exile another target nonland permanent.
When Oblivion Ring leaves the battlefield, return the exiled card to the battlefield under its owner's control.

Swamp

Chromatic Lantern

Lands you control have "{T}: Add one mana of any color."
{T}: Add one mana of any color.

Smoldering Marsh

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

Wrathful Red Dragon

Flying
Whenever a Dragon you control is dealt damage, it deals that much damage to any target that isn't a Dragon.

Canyon Slough

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

Sacred Foundry

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

Grasp of Fate

When Grasp of Fate enters, for each opponent, exile up to one target nonland permanent that player controls until Grasp of Fate leaves the battlefield. (Those permanents return under their owners' control.)

Ancient Runes

At the beginning of each player's upkeep, Ancient Runes deals damage to that player equal to the number of artifacts they control.

Brotherhood's End

Choose one —
• Brotherhood's End deals 3 damage to each creature and each planeswalker.
• Destroy all artifacts with mana value 3 or less.

Rolling Earthquake

Rolling Earthquake deals X damage to each creature without horsemanship and each player.

Stranglehold

Your opponents can't search libraries.
If an opponent would begin an extra turn, that player skips that turn instead.

Snowfield Sinkhole

({T}: Add {W} or {B}.)
Snowfield Sinkhole enters tapped.

Spiteful Sliver

Sliver creatures you control have "Whenever this creature is dealt damage, it deals that much damage to target player or planeswalker."

Mogg Maniac

Whenever Mogg Maniac is dealt damage, it deals that much damage to target opponent or planeswalker.

Sun Titan

Vigilance
Whenever Sun Titan enters or attacks, you may return target permanent card with mana value 3 or less from your graveyard to the battlefield.

Avacyn, Angel of Hope

Flying, vigilance, indestructible
Other permanents you control have indestructible.

Metropolis Reformer

Flying, vigilance
You have hexproof.
Whenever Metropolis Reformer is dealt damage, you gain that much life.

Sol Ring

Shielded by Faith

Enchant creature
Enchanted creature has indestructible.
Whenever a creature enters, you may attach Shielded by Faith to that creature.

Wildfire

Each player sacrifices four lands. Wildfire deals 4 damage to each creature.

Replenish

Return all enchantment cards from your graveyard to the battlefield. (Auras with nothing to enchant remain in your graveyard.)

Spectator Seating

Spectator Seating enters tapped unless you have two or more opponents.
{T}: Add {R} or {W}.

Pain Distributor

Menace
Whenever a player casts their first spell each turn, they create a Treasure token.
Whenever an artifact an opponent controls is put into a graveyard from the battlefield, Pain Distributor deals 1 damage to that player.

Blasphemous Act

This spell costs {1} less to cast for each creature on the battlefield.
Blasphemous Act deals 13 damage to each creature.

Enlightened Tutor

Search your library for an artifact or enchantment card, reveal it, then shuffle and put that card on top.

Exotic Orchard

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

Godless Shrine

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

Queen Marchesa

Deathtouch, haste
When Queen Marchesa enters, you become the monarch.
At the beginning of your upkeep, if an opponent is the monarch, create a 1/1 black Assassin creature token with deathtouch and haste.

Brash Taunter

Indestructible
Whenever Brash Taunter is dealt damage, it deals that much damage to target opponent.
{2}{R}, {T}: Brash Taunter fights another target creature.

Spiteful Visions

At the beginning of each player's draw step, that player draws an additional card.
Whenever a player draws a card, Spiteful Visions deals 1 damage to that player.

Wave of Reckoning

Each creature deals damage to itself equal to its power.

Last Laugh

Whenever a permanent other than Last Laugh is put into a graveyard from the battlefield, Last Laugh deals 1 damage to each creature and each player.
When no creatures are on the battlefield, sacrifice Last Laugh.

Sundown Pass

Sundown Pass enters tapped unless you control two or more other lands.
{T}: Add {R} or {W}.

Resurgent Belief

Suspend 2—{1}{W} (Rather than cast this card from your hand, pay {1}{W} and exile it with two time counters on it. At the beginning of your upkeep, remove a time counter. When the last is removed, you may cast it without paying its mana cost.)
Return all enchantment cards from your graveyard to the battlefield. (Auras with nothing to enchant remain in your graveyard.)

Chain Reaction

Chain Reaction deals X damage to each creature, where X is the number of creatures on the battlefield.

Star of Extinction

Destroy target land. Star of Extinction deals 20 damage to each creature and each planeswalker.

Forbidden Orchard

{T}: Add one mana of any color.
Whenever you tap Forbidden Orchard for mana, target opponent creates a 1/1 colorless Spirit creature token.

Blood Crypt

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

Maralen of the Mornsong

Players can't draw cards.
At the beginning of each player's draw step, that player loses 3 life, searches their library for a card, puts it into their hand, then shuffles.

Smothering Tithe

Whenever an opponent draws a card, that player may pay {2}. If the player doesn't, you create a Treasure token. (It's an artifact with "{T}, Sacrifice this artifact: Add one mana of any color.")

Mount Doom

{T}, Pay 1 life: Add {B} or {R}.
{1}{B}{R}, {T}: Mount Doom deals 1 damage to each opponent.
{5}{B}{R}, {T}, Sacrifice Mount Doom and a legendary artifact: Choose up to two creatures, then destroy the rest. Activate only as a sorcery.

Pyrohemia

At the beginning of the end step, if no creatures are on the battlefield, sacrifice Pyrohemia.
{R}: Pyrohemia deals 1 damage to each creature and each player.

Boros Signet

Boros Reckoner

Whenever Boros Reckoner is dealt damage, it deals that much damage to any target.
{R/W}: Boros Reckoner gains first strike until end of turn.

Phyrexian Vindicator

Flying
If damage would be dealt to Phyrexian Vindicator, prevent that damage. When damage is prevented this way, Phyrexian Vindicator deals that much damage to any other target.

Darksteel Mutation

Enchant creature
Enchanted creature is an Insect artifact creature with base power and toughness 0/1 and has indestructible, and it loses all other abilities, card types, and creature types.

Alpine Meadow

({T}: Add {R} or {W}.)
Alpine Meadow enters tapped.

Terramorphic Expanse

{T}, Sacrifice Terramorphic Expanse: Search your library for a basic land card, put it onto the battlefield tapped, then shuffle.

Spitemare

Whenever Spitemare is dealt damage, it deals that much damage to any target.

Sacred Peaks

({T}: Add {R} or {W}.)
Sacred Peaks enters tapped.

Structural Assault

Destroy all artifacts, then Structural Assault deals damage to each creature equal to the number of artifacts that were put into graveyards from the battlefield this turn.

Repercussion

Whenever a creature is dealt damage, Repercussion deals that much damage to that creature's controller.

Inspiring Vantage

Inspiring Vantage enters tapped unless you control two or fewer other lands.
{T}: Add {R} or {W}.

Veinfire Borderpost

You may pay {1} and return a basic land you control to its owner's hand rather than pay this spell's mana cost.
Veinfire Borderpost enters tapped.
{T}: Add {B} or {R}.

Caves of Koilos

{T}: Add {C}.
{T}: Add {W} or {B}. Caves of Koilos deals 1 damage to you.

Dragonskull Summit

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

Deafening Clarion

Choose one or both —
• Deafening Clarion deals 3 damage to each creature.
• Creatures you control gain lifelink until end of turn.

Obliterate

This spell can't be countered.
Destroy all artifacts, creatures, and lands. They can't be regenerated.

Boros Charm

Choose one —
• Boros Charm deals 4 damage to target player or planeswalker.
• Permanents you control gain indestructible until end of turn.
• Target creature gains double strike until end of turn.

No Mercy

Whenever a creature deals damage to you, destroy it.

Doom Foretold

At the beginning of each player's upkeep, that player sacrifices a nonland, nontoken permanent. If that player can't, they discard a card, they lose 2 life, you draw a card, you gain 2 life, you create a 2/2 white Knight creature token with vigilance, then you sacrifice Doom Foretold.

Command Tower

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

Plains

Arcbond

Choose target creature. Whenever that creature is dealt damage this turn, it deals that much damage to each other creature and each player.

Forsaken Wastes

Players can't gain life.
At the beginning of each player's upkeep, that player loses 1 life.
Whenever Forsaken Wastes becomes the target of a spell, that spell's controller loses 5 life.

Savai Triome

({T}: Add {R}, {W}, or {B}.)
Savai Triome enters tapped.
Cycling {3} ({3}, Discard this card: Draw a card.)

Arcane Signet

Triskaidekaphobia

At the beginning of your upkeep, choose one —
• Each player with exactly 13 life loses the game, then each player gains 1 life.
• Each player with exactly 13 life loses the game, then each player loses 1 life.

Needle Spires

Needle Spires enters tapped.
{T}: Add {R} or {W}.
{2}{R}{W}: Needle Spires becomes a 2/1 red and white Elemental creature with double strike until end of turn. It's still a land.

Battlefield Forge

{T}: Add {C}.
{T}: Add {R} or {W}. Battlefield Forge deals 1 damage to you.

Price of Glory

Whenever a player taps a land for mana, if it's not that player's turn, destroy that land.

Geothermal Bog

({T}: Add {B} or {R}.)
Geothermal Bog enters tapped.

Roiling Vortex

At the beginning of each player's upkeep, Roiling Vortex deals 1 damage to them.
Whenever a player casts a spell, if no mana was spent to cast that spell, Roiling Vortex deals 5 damage to that player.
{R}: Your opponents can't gain life this turn.

Destructive Force

Each player sacrifices five lands. Destructive Force deals 5 damage to each creature.

Havoc Festival

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

Orzhov Signet

Descent into Avernus

At the beginning of your upkeep, put two descent counters on Descent into Avernus. Then each player creates X Treasure tokens and Descent into Avernus deals X damage to each player, where X is the number of descent counters on Descent into Avernus.

Truefire Captain

Mentor (Whenever this creature attacks, put a +1/+1 counter on target attacking creature with lesser power.)
Whenever Truefire Captain is dealt damage, it deals that much damage to target player.

Marchesa, Resolute Monarch

Menace, deathtouch
Whenever Marchesa, Resolute Monarch attacks, remove all counters from up to one target permanent.
At the beginning of your upkeep, if you haven't been dealt combat damage since your last turn, you draw a card and you lose 1 life.

Invasion of Fiora

(As a Siege enters, choose an opponent to protect it. You and others can attack it. When it's defeated, exile it, then cast it transformed.)
When Invasion of Fiora enters, choose one or both —
• Destroy all legendary creatures.
• Destroy all nonlegendary creatures.

Invasion of Fiora // Marchesa, Resolute Monarch

Coalhauler Swine

Whenever Coalhauler Swine is dealt damage, it deals that much damage to each player.

Solar Blaze

Painful Quandary

Whenever an opponent casts a spell, that player loses 5 life unless they discard a card.

Nomad Outpost

Nomad Outpost enters tapped.
{T}: Add {R}, {W}, or {B}.

Rakdos Signet

Howlpack Avenger

Whenever a permanent you control is dealt damage, Howlpack Avenger deals that much damage to any target.
{1}{R}: Howlpack Avenger gets +2/+0 until end of turn.
Nightbound (If a player casts at least two spells during their own turn, it becomes day next turn.)

Ill-Tempered Loner

Whenever Ill-Tempered Loner is dealt damage, it deals that much damage to any target.
{1}{R}: Ill-Tempered Loner gets +2/+0 until end of turn.
Daybound (If a player casts no spells during their own turn, it becomes night next turn.)