Zo-Zu the Punisher

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

Fire Servant

If a red instant or sorcery spell you control would deal damage, it deals double that damage instead.

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.

Circle of Flame

Whenever a creature without flying attacks you or a planeswalker you control, Circle of Flame deals 1 damage to that creature.

Immolation Shaman

Whenever an opponent activates an ability of an artifact, creature, or land that isn't a mana ability, Immolation Shaman deals 1 damage to that player.
{3}{R}{R}: Immolation Shaman gets +3/+3 and gains menace until end of turn.

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.

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.

Burnished Hart

{3}, Sacrifice Burnished Hart: Search your library for up to two basic land cards, put them onto the battlefield tapped, then shuffle.

Spellshock

Whenever a player casts a spell, Spellshock deals 2 damage to that player.

Smelt

Mountain

Slagstorm

Choose one —
• Slagstorm deals 3 damage to each creature.
• Slagstorm deals 3 damage to each player.

Magus of the Wheel

{1}{R}, {T}, Sacrifice Magus of the Wheel: Each player discards their hand, then draws seven cards.

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.

Lightning Bolt

Lightning Bolt deals 3 damage to any target.

Manabarbs

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

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.

Blazing Volley

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

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.")

Aether Sting

Whenever an opponent casts a creature spell, Aether Sting deals 1 damage to that player.

Price of Progress

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

Mizzium Mortars

Mizzium Mortars deals 4 damage to target creature you don't control.
Overload {3}{R}{R}{R} (You may cast this spell for its overload cost. If you do, change "target" in its text to "each.")

Flame Rift

Flame Rift deals 4 damage to each player.

Fanatic of Mogis

When Fanatic of Mogis 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.)

Rampaging Ferocidon

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

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.

Solemn Simulacrum

When Solemn Simulacrum enters, you may search your library for a basic land card, put that card onto the battlefield tapped, then shuffle.
When Solemn Simulacrum dies, you may draw a card.

Leyline of Punishment

If Leyline of Punishment is in your opening hand, you may begin the game with it on the battlefield.
Players can't gain life.
Damage can't be prevented.

Thermo-Alchemist

Defender
{T}: Thermo-Alchemist deals 1 damage to each opponent.
Whenever you cast an instant or sorcery spell, untap Thermo-Alchemist.

Tibalt, Rakish Instigator

Your opponents can't gain life.
−2: Create a 1/1 red Devil creature token with "When this creature dies, it deals 1 damage to any target."

Guttersnipe

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

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.")

Earthquake

Earthquake deals X damage to each creature without flying and each player.

Scorching Dragonfire

Scorching Dragonfire deals 3 damage to target creature or planeswalker. If that creature or planeswalker would die this turn, exile it instead.

Tormenting Voice

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

Volcanic Fallout

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

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.)

Seismic Strike

Seismic Strike deals damage to target creature equal to the number of Mountains you control.

Smash to Smithereens

Destroy target artifact. Smash to Smithereens deals 3 damage to that artifact's controller.

Chandra, Heart of Fire

+1: Discard your hand, then exile the top three cards of your library. Until end of turn, you may play cards exiled this way.
+1: Chandra, Heart of Fire deals 2 damage to any target.
−9: Search your graveyard and library for any number of red instant and/or sorcery cards, exile them, then shuffle. You may cast them this turn. Add six {R}.

Chandra, Roaring Flame

+1: Chandra, Roaring Flame deals 2 damage to target player or planeswalker.
−2: Chandra, Roaring Flame deals 2 damage to target creature.
−7: Chandra, Roaring Flame 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, Fire of Kaladesh.
{T}: Chandra, Fire of Kaladesh 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

Sol Ring

Chandra's Incinerator

This spell costs {X} less to cast, where X is the total amount of noncombat damage dealt to your opponents this turn.
Trample
Whenever a source you control deals noncombat damage to an opponent, Chandra's Incinerator deals that much damage to target creature or planeswalker that player controls.

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.

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.

Staff of Nin

At the beginning of your upkeep, draw a card.
{T}: Staff of Nin deals 1 damage to any target.

Injury

Aftermath (Cast this spell only from your graveyard. Then exile it.)
Injury deals 2 damage to target creature and 2 damage to target player or planeswalker.

Insult

Damage can't be prevented this turn. If a source you control would deal damage this turn, it deals double that damage instead.

Insult // Injury

Transmogrify

Exile target creature. That creature's controller reveals cards from the top of their library until they reveal a creature card. That player puts that card onto the battlefield, then shuffles the rest into their library.

Jaya, Venerated Firemage

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.
−2: Jaya, Venerated Firemage deals 2 damage to any target.

Browbeat

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

Burning Earth

Whenever a player taps a nonbasic land for mana, Burning Earth deals 1 damage to that player.

Syr Carah, the Bold

Whenever Syr Carah, the Bold or an instant or sorcery spell you control deals damage to a player, exile the top card of your library. You may play that card this turn.
{T}: Syr Carah deals 1 damage to any target.

Firebrand Archer

Whenever you cast a noncreature spell, Firebrand Archer deals 1 damage to each opponent.

Angrath's Marauders

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

Thrill of Possibility

Shock

Abrade

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

Harsh Mentor

Whenever an opponent activates an ability of an artifact, creature, or land on the battlefield, if it isn't a mana ability, Harsh Mentor deals 2 damage to that player.

Electrostatic Field

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

Ankh of Mishra

Whenever a land enters, Ankh of Mishra deals 2 damage to that land's controller.

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.

Goblin Chainwhirler

First strike
When Goblin Chainwhirler enters, it deals 1 damage to each opponent and each creature and planeswalker they control.

Double Vision

Whenever you cast your first instant or sorcery spell each turn, copy that spell. You may choose new targets for the copy.

Cinder Pyromancer

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

Forgotten Cave

Forgotten Cave enters tapped.
{T}: Add {R}.
Cycling {R} ({R}, Discard this card: Draw a card.)

Light Up the Stage

Spectacle {R} (You may cast this spell for its spectacle cost rather than its mana cost if an opponent lost life this turn.)
Exile the top two cards of your library. Until the end of your next turn, you may play those cards.