Nykthos, Shrine to Nyx

{T}: Add {C}.
{2}, {T}: Choose a color. Add an amount of mana of that color equal to your devotion to that color. (Your devotion to a color is the number of mana symbols of that color in the mana costs of permanents you control.)

Firebrand Archer

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

Spear Spewer

Defender
{T}: This creature deals 1 damage to each player.

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.

Fiery Emancipation

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

Guttersnipe

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

Neheb, the Eternal

Afflict 3 (Whenever this creature becomes blocked, defending player loses 3 life.)
At the beginning of each of your postcombat main phases, add {R} for each 1 life your opponents have lost this turn.

Wheel of Fortune

Each player discards their hand, then draws seven cards.

Sokenzan, Crucible of Defiance

{T}: Add {R}.
Channel — {3}{R}, Discard this card: Create two 1/1 colorless Spirit creature tokens. They gain haste until end of turn. This ability costs {1} less to activate for each legendary creature you control.

Fiery Confluence

Choose three. You may choose the same mode more than once.
• Fiery Confluence deals 1 damage to each creature.
• Fiery Confluence deals 2 damage to each opponent.
• Destroy target artifact.

Burning Earth

Whenever a player taps a nonbasic land for mana, this enchantment deals 1 damage to that player.

Runaway Steam-Kin

Whenever you cast a red spell, if this creature has fewer than three +1/+1 counters on it, put a +1/+1 counter on this creature.
Remove three +1/+1 counters from this creature: Add {R}{R}{R}.

Great Furnace

Reliquary Tower

You have no maximum hand size.
{T}: Add {C}.

Heartless Hidetsugu

{T}: Heartless Hidetsugu deals damage to each player equal to half that player's life total, rounded down.

Manabarbs

Whenever a player taps a land for mana, this enchantment deals 1 damage to that player.

Abrade

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

Shinka, the Bloodsoaked Keep

{T}: Add {R}.
{R}, {T}: Target legendary creature gains first strike until end of turn.

Browbeat

Any player may have Browbeat deal 5 damage to them. If no one does, target player draws three cards.

Volcanic Fallout

This spell can't be countered.
Volcanic Fallout deals 2 damage to each creature and each player.

Price of Progress

Price of Progress deals damage to each player equal to twice the number of nonbasic lands that player controls.

Risk Factor

Target opponent may have Risk Factor deal 4 damage to them. If that player doesn't, you draw three cards.
Jump-start (You may cast this card from your graveyard by discarding a card in addition to paying its other costs. Then exile this card.)

Inferno Titan

{R}: This creature gets +1/+0 until end of turn.
Whenever this creature enters or attacks, it deals 3 damage divided as you choose among one, two, or three targets.

Reflecting Pool

{T}: Add one mana of any type that a land you control could produce.

Pyromancer's Goggles

{T}: Add {R}. When that mana is spent to cast a red instant or sorcery spell, copy that spell and you may choose new targets for the copy.

Electrickery

Electrickery deals 1 damage to target creature you don't control.
Overload {1}{R} (You may cast this spell for its overload cost. If you do, change "target" in its text to "each.")

The Grey Havens

When The Grey Havens enters, scry 1.
{T}: Add {C}.
{T}: Add one mana of any color among legendary creature cards in your graveyard.

Zo-Zu the Punisher

Whenever a land enters, Zo-Zu deals 2 damage to that land's controller.

Sulfuric Vortex

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

Ruby Medallion

Red spells you cast cost {1} less to cast.

Desert

{T}: Add {C}.
{T}: This land deals 1 damage to target attacking creature. Activate only during the end of combat step.

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.

Razorkin Needlehead

This creature has first strike during your turn.
Whenever an opponent draws a card, this creature deals 1 damage to them.

Hazoret's Monument

Red creature spells you cast cost {1} less to cast.
Whenever you cast a creature spell, you may discard a card. If you do, draw a card.

Sol Ring

Chandra, Roaring Flame

+1: Chandra deals 2 damage to target player or planeswalker.
−2: Chandra deals 2 damage to target creature.
−7: Chandra deals 6 damage to each opponent. Each player dealt damage this way gets an emblem with "At the beginning of your upkeep, this emblem deals 3 damage to you."

Chandra, Fire of Kaladesh

Whenever you cast a red spell, untap Chandra.
{T}: Chandra deals 1 damage to target player or planeswalker. If Chandra has dealt 3 or more damage this turn, exile her, then return her to the battlefield transformed under her owner's control.

Chandra, Fire of Kaladesh // Chandra, Roaring Flame

The Mycosynth Gardens

{T}: Add {C}.
{1}, {T}: Add one mana of any color.
{X}, {T}: This land becomes a copy of target nontoken artifact you control with mana value X.

Kessig Flamebreather

Fellwar Stone

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

End the Festivities

End the Festivities deals 1 damage to each opponent and each creature and planeswalker they control.

Boltwave

Boltwave deals 3 damage to each opponent.

Solphim, Mayhem Dominus

If a source you control would deal noncombat damage to an opponent or a permanent an opponent controls, it deals double that damage to that player or permanent instead.
{1}{R/P}{R/P}, Discard two cards: Put an indestructible counter on Solphim. ({R/P} can be paid with either {R} or 2 life.)

Flame Rift

Flame Rift deals 4 damage to each player.

Shock

Pyrohemia

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

Chandra, Torch of Defiance

+1: Exile the top card of your library. You may cast that card. If you don't, Chandra deals 2 damage to each opponent.
+1: Add {R}{R}.
−3: Chandra deals 4 damage to target creature.
−7: You get an emblem with "Whenever you cast a spell, this emblem deals 5 damage to any target."

Unruly Catapult

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

Moonsilver Key

{1}, {T}, Sacrifice this artifact: Search your library for an artifact card with a mana ability or a basic land card, reveal it, put it into your hand, then shuffle.

Commander's Sphere

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

The One Ring

Indestructible
When The One Ring enters, if you cast it, you gain protection from everything until your next turn.
At the beginning of your upkeep, you lose 1 life for each burden counter on The One Ring.
{T}: Put a burden counter on The One Ring, then draw a card for each burden counter on The One Ring.

Jeska's Will

Choose one. If you control a commander as you cast this spell, you may choose both instead.
• Add {R} for each card in target opponent's hand.
• Exile the top three cards of your library. You may play them this turn.

Lightning Strike

Lightning Strike deals 3 damage to any target.

War Room

{T}: Add {C}.
{3}, {T}, Pay life equal to the number of colors in your commanders' color identity: Draw a card.

Tectonic Giant

Whenever this creature attacks or becomes the target of a spell an opponent controls, choose one —
• This creature deals 3 damage to each opponent.
• Exile the top two cards of your library. Choose one of them. Until the end of your next turn, you may play that card.

Fanatic of Mogis

When this creature enters, it deals damage to each opponent equal to your devotion to red. (Each {R} in the mana costs of permanents you control counts toward your devotion to red.)

Thrill of Possibility

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

Command Tower

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

Throne of Eldraine

As Throne of Eldraine enters, choose a color.
{T}: Add four mana of the chosen color. Spend this mana only to cast monocolored spells of that color.
{3}, {T}: Draw two cards. Spend only mana of the chosen color to activate this ability.

Mountain

Arcane Signet

Inventors' Fair

At the beginning of your upkeep, if you control three or more artifacts, you gain 1 life.
{T}: Add {C}.
{4}, {T}, Sacrifice Inventors' Fair: Search your library for an artifact card, reveal it, put it into your hand, then shuffle. Activate only if you control three or more artifacts.

Rampaging Ferocidon

Menace
Players can't gain life.
Whenever another creature enters, this creature deals 1 damage to that creature's controller.

Blood Moon

Blazing Volley

Blazing Volley deals 1 damage to each creature your opponents control.

Treasure

{T}, Sacrifice this token: Add one mana of any color.

Embermaw Hellion

Trample (This creature can deal excess combat damage to the player or planeswalker it's attacking.)
If another red source you control would deal damage to a permanent or player, it deals that much damage plus 1 to that permanent or player instead.

Purphoros, God of the Forge

Indestructible
As long as your devotion to red is less than five, Purphoros isn't a creature.
Whenever another creature you control enters, Purphoros deals 2 damage to each opponent.
{2}{R}: Creatures you control get +1/+0 until end of turn.

Ancient Ziggurat

{T}: Add one mana of any color. Spend this mana only to cast a creature spell.

Electrostatic Field

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

Fire Diamond

This artifact enters tapped.
{T}: Add {R}.

Valakut, the Molten Pinnacle

This land enters tapped.
Whenever a Mountain you control enters, if you control at least five other Mountains, you may have this land deal 3 damage to any target.
{T}: Add {R}.

Roiling Vortex

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

Tectonic Hazard

Tectonic Hazard deals 1 damage to each opponent and each creature they control.

Wheel of Misfortune

Each player secretly chooses a number 0 or greater, then all players reveal those numbers simultaneously and determine the highest and lowest numbers revealed this way. Wheel of Misfortune deals damage equal to the highest number to each player who chose that number. Each player who didn't choose the lowest number discards their hand, then draws seven cards.

Mana Vault

This artifact doesn't untap during your untap step.
At the beginning of your upkeep, you may pay {4}. If you do, untap this artifact.
At the beginning of your draw step, if this artifact is tapped, it deals 1 damage to you.
{T}: Add {C}{C}{C}.

Torbran, Thane of Red Fell

If a red source you control would deal damage to an opponent or a permanent an opponent controls, it deals that much damage plus 2 instead.

Blasphemous Act

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

Thermo-Alchemist

Cinder Pyromancer

{T}: This creature deals 1 damage to target player or planeswalker.
Whenever you cast a red spell, you may untap this creature.

Homeward Path

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

Lightning Bolt

Lightning Bolt deals 3 damage to any target.

Temple of Power

(Transforms from Ojer Axonil, Deepest Might.)
{T}: Add {R}.
{2}{R}, {T}: Transform this land. Activate only if red sources you controlled dealt 4 or more noncombat damage this turn and only as a sorcery.

Ojer Axonil, Deepest Might

Trample
If a red source you control would deal an amount of noncombat damage less than Ojer Axonil's power to an opponent, that source deals damage equal to Ojer Axonil's power instead.
When Ojer Axonil dies, return it to the battlefield tapped and transformed under its owner's control.

Ojer Axonil, Deepest Might // Temple of Power

Arena of Glory

This land enters tapped unless you control a Mountain.
{T}: Add {R}.
{R}, {T}, Exert this land: Add {R}{R}. If that mana is spent on a creature spell, it gains haste until end of turn. (An exerted permanent won't untap during your next untap step.)

Deserted Temple

{T}: Add {C}.
{1}, {T}: Untap target land.

Mechanized Warfare

If a red or artifact source you control would deal damage to an opponent or a permanent an opponent controls, it deals that much damage plus 1 instead.

Urza's Saga

(As this Saga enters and after your draw step, add a lore counter. Sacrifice after III.)
I — This Saga gains "{T}: Add {C}."
II — This Saga gains "{2}, {T}: Create a 0/0 colorless Construct artifact creature token with 'This token gets +1/+1 for each artifact you control.'"
III — Search your library for an artifact card with mana cost {0} or {1}, put it onto the battlefield, then shuffle.

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.")

Descent into Avernus

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