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.

Unruly Catapult

Defender
{T}: This creature deals 1 damage to each opponent.
Whenever you cast an instant or sorcery spell, untap this creature.

Ensnared by the Mara

Each opponent faces a villainous choice — They exile cards from the top of their library until they exile a nonland card, then you may cast that card without paying its mana cost, or that player exiles the top four cards of their library and Ensnared by the Mara deals damage equal to the total mana value of those exiled cards to that player.

Firebrand Archer

Whenever you cast a noncreature spell, this creature deals 1 damage to each opponent.

Talisman of Indulgence

{T}: Add {C}.
{T}: Add {B} or {R}. This artifact deals 1 damage to you.

Swamp

Erebor Flamesmith

Whenever you cast an instant or sorcery spell, this creature deals 1 damage to each opponent.

Fellwar Stone

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

Rakdos Signet

Infernal Grasp

Destroy target creature. You lose 2 life.

Queen Brahne

Prowess
Whenever Queen Brahne attacks, create a 0/1 black Wizard creature token with "Whenever you cast a noncreature spell, this token deals 1 damage to each opponent."

Big Score

As an additional cost to cast this spell, discard a card.
Draw two cards and create two Treasure tokens. (They're artifacts with "{T}, Sacrifice this token: Add one mana of any color.")

Far Fortune, End Boss

Start your engines! (If you have no speed, it starts at 1. It increases once on each of your turns when an opponent loses life. Max speed is 4.)
Whenever you attack, Far Fortune deals 1 damage to each opponent.
Max speed — If a source you control would deal damage to an opponent or a permanent an opponent controls, it deals that much damage plus 1 instead.

Foreboding Ruins

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

Go for the Throat

Thermo-Alchemist

Thrill of Possibility

As an additional cost to cast this spell, discard a card.
Draw two cards.

Feed the Swarm

Destroy target creature or enchantment an opponent controls. You lose life equal to that permanent's mana value.

Pact of the Serpent

Choose a creature type. Target player draws X cards and loses X life, where X is the number of creatures they control of the chosen type.

Command Tower

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

Fiendish Duo

First strike (This creature deals combat damage before creatures without first strike.)
If a source would deal damage to an opponent, it deals double that damage to that player instead.

Ambition's Cost

You draw three cards and you lose 3 life.

Fiery Inscription

When this enchantment enters, the Ring tempts you.
Whenever you cast an instant or sorcery spell, this enchantment deals 2 damage to each opponent.

Transpose

Draw a card, then discard a card. You lose 1 life. If this spell was cast from your hand, create a 0/1 black Wizard creature token with "Whenever you cast a noncreature spell, this token deals 1 damage to each opponent."
Rebound (If you cast this spell from your hand, exile it as it resolves. At the beginning of your next upkeep, you may cast this card from exile without paying its mana cost.)

Dragonskull Summit

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

Faithless Looting

Draw two cards, then discard two cards.
Flashback {2}{R} (You may cast this card from your graveyard for its flashback cost. Then exile it.)

Grab the Prize

As an additional cost to cast this spell, discard a card.
Draw two cards. If the discarded card wasn't a land card, Grab the Prize deals 2 damage to each opponent.

Read the Bones

Scry 2, then draw two cards. You lose 2 life. (To scry 2, look at the top two cards of your library, then put any number of them on the bottom and the rest on top in any order.)

Trance Kuja, Fate Defied

Flame Star — If a Wizard you control would deal damage to a permanent or player, it deals double that damage instead.

Kuja, Genome Sorcerer

At the beginning of your end step, create a tapped 0/1 black Wizard creature token with "Whenever you cast a noncreature spell, this token deals 1 damage to each opponent." Then if you control four or more Wizards, transform Kuja.

Kuja, Genome Sorcerer // Trance Kuja, Fate Defied

Terminate

Destroy target creature. It can't be regenerated.

Rankle and Torbran

Flying, first strike, haste
Whenever Rankle and Torbran deals combat damage to a player or battle, choose any number —
• Each player creates a Treasure token.
• Each player sacrifices a creature of their choice.
• If a source would deal damage to a player or battle this turn, it deals that much damage plus 2 instead.

Coruscation Mage

Offspring {2} (You may pay an additional {2} as you cast this spell. If you do, when this creature enters, create a 1/1 token copy of it.)
Whenever you cast a noncreature spell, this creature deals 1 damage to each opponent.

Arcane Signet

Corrupted Conviction

As an additional cost to cast this spell, sacrifice a creature.
Draw two cards.

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.

Shadowblood Ridge

Terramorphic Expanse

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

Circle of Power

You draw two cards and you lose 2 life. Create a 0/1 black Wizard creature token with "Whenever you cast a noncreature spell, this token deals 1 damage to each opponent."
Wizards you control get +1/+0 and gain lifelink until end of turn.

Deadly Dispute

As an additional cost to cast this spell, sacrifice an artifact or creature.
Draw two cards and create a Treasure token. (It's an artifact with "{T}, Sacrifice this token: Add one mana of any color.")

Black Waltz No. 3

Flying, deathtouch
Whenever you cast a noncreature spell, Black Waltz No. 3 deals 2 damage to each opponent.

Exotic Orchard

Night's Whisper

Guttersnipe

Whenever you cast an instant or sorcery spell, this creature deals 2 damage to each opponent.

Mountain

Rockslide Sorcerer

Whenever you cast an instant, sorcery, or Wizard spell, this creature deals 1 damage to any target.

Firespitter Whelp

Flying
Whenever you cast a noncreature or Dragon spell, this creature deals 1 damage to each opponent.

Abrade

Choose one —
• Abrade deals 3 damage to target creature.
• Destroy target artifact.

Tor Wauki the Younger

Reach, lifelink
If another source you control would deal noncombat damage to a permanent or player, it deals that much damage plus 1 to that permanent or player instead.
Whenever you cast an instant or sorcery spell, Tor Wauki deals 2 damage to any target.

Rakdos Carnarium

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

Mage Siege

Create a 0/1 black Wizard creature token with "Whenever you cast a noncreature spell, this token deals 1 damage to each opponent."

Lindblum, Industrial Regency

Lindblum, Industrial Regency // Mage Siege

Bedevil

Destroy target artifact, creature, or planeswalker.

Chain Reaction

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

Diresight

Surveil 2, then draw two cards. You lose 2 life. (To surveil 2, look at the top two cards of your library, then put any number of them into your graveyard and the rest on top of your library in any order.)

Gratuitous Violence

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

Myriad Landscape

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

Molten Gatekeeper

Whenever another creature you control enters, this creature deals 1 damage to each opponent.
Unearth {R} ({R}: Return this card from your graveyard to the battlefield. It gains haste. Exile it at the beginning of the next end step or if it would leave the battlefield. Unearth only as a sorcery.)

Disrupt Decorum

Goad all creatures you don't control. (Until your next turn, those creatures attack each combat if able and attack a player other than you if able.)

Smoldering Marsh

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

Evolving Wilds

Shivan Gorge

{T}: Add {C}.
{2}{R}, {T}: Shivan Gorge deals 1 damage to each opponent.

Sorcerer's Wand

Equipped creature has "{T}: This creature deals 1 damage to target player or planeswalker. If this creature is a Wizard, it deals 2 damage instead."
Equip {3}

Sulfurous Mire

({T}: Add {B} or {R}.)
This land enters tapped.

Overkill

Target creature gets -0/-9999 until end of turn.

Tainted Peak

{T}: Add {C}.
{T}: Add {B} or {R}. Activate only if you control a Swamp.

Aether Revolt

Revolt — As long as a permanent left the battlefield under your control this turn, if a source you control would deal noncombat damage to an opponent or a permanent an opponent controls, it deals that much damage plus 2 instead.
Whenever you get one or more {E}, this enchantment deals that much damage to any target.

Electrostatic Field

Defender
Whenever you cast an instant or sorcery spell, this creature deals 1 damage to each opponent.

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.")

Canyon Slough

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

Sol Ring

Mysidian Elder

When this creature enters, create a 0/1 black Wizard creature token with "Whenever you cast a noncreature spell, this token deals 1 damage to each opponent."

Path of Ancestry

This land enters tapped.
{T}: Add one mana of any color in your commander's color identity. When that mana is spent to cast a creature spell that shares a creature type with your commander, scry 1. (Look at the top card of your library. You may put that card on the bottom.)

Volcanic Torrent

Cascade (When you cast this spell, exile cards from the top of your library until you exile a nonland card that costs less. You may cast it without paying its mana cost. Put the exiled cards on the bottom in a random order.)
Volcanic Torrent deals X damage to each creature and planeswalker your opponents control, where X is the number of spells you've cast this turn.

Sign in Blood

Target player draws two cards and loses 2 life.

Dark Ritual

Syphon Mind

Each other player discards a card. You draw a card for each card discarded this way.

Geothermal Bog

Kardur, Doomscourge

When Kardur enters, until your next turn, creatures your opponents control attack each combat if able and attack a player other than you if able.
Whenever an attacking creature dies, each opponent loses 1 life and you gain 1 life.

Village Rites

Cornered by Black Mages

Target opponent sacrifices a creature of their choice.
Create a 0/1 black Wizard creature token with "Whenever you cast a noncreature spell, this token deals 1 damage to each opponent."

Judith, Carnage Connoisseur

Whenever you cast an instant or sorcery spell, choose one —
• That spell gains deathtouch and lifelink.
• Create a 2/2 red Imp creature token with "When this token dies, it deals 2 damage to each opponent."

Sulfurous Springs

{T}: Add {C}.
{T}: Add {B} or {R}. This land deals 1 damage to you.

Black Mage's Rod

Job select (When this Equipment enters, create a 1/1 colorless Hero creature token, then attach this to it.)
Equipped creature gets +1/+0, has "Whenever you cast a noncreature spell, this creature deals 1 damage to each opponent," and is a Wizard in addition to its other types.
Equip {3}

Witty Roastmaster

Alliance — Whenever another creature you control enters, this creature deals 1 damage to each opponent.

Fandaniel, Telophoroi Ascian

Whenever you cast an instant or sorcery spell, surveil 1.
At the beginning of your end step, each opponent may sacrifice a nontoken creature of their choice. Each opponent who doesn't loses 2 life for each instant and sorcery card in your graveyard.

Temple of Malice

This land enters tapped.
When this land enters, scry 1. (Look at the top card of your library. You may put that card on the bottom.)
{T}: Add {B} or {R}.