Runaway Steam-Kin

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

Dragon's Claw

Whenever a player casts a red spell, you may gain 1 life.

Jaxis, the Troublemaker

{R}, {T}, Discard a card: Create a token that's a copy of another target creature you control. It gains haste and "When this creature dies, draw a card." Sacrifice it at the beginning of the next end step. Activate only as a sorcery.
Blitz {1}{R} (If you cast this spell for its blitz cost, it gains haste and "When this creature dies, draw a card." Sacrifice it at the beginning of the next end step.)

Zoyowa Lava-Tongue

Deathtouch
At the beginning of your end step, if you descended this turn, each opponent may discard a card or sacrifice a permanent of their choice. Zoyowa Lava-Tongue deals 3 damage to each opponent who didn't. (You descended if a permanent card was put into your graveyard from anywhere.)

Guttersnipe

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

Bond of Revival

Return target creature card from your graveyard to the battlefield. It gains haste until your next turn.

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.

Nadier, Agent of the Duskenel

Whenever a token you control leaves the battlefield, put a +1/+1 counter on Nadier, Agent of the Duskenel.
When Nadier leaves the battlefield, create a number of 1/1 green Elf Warrior creature tokens equal to its power.
Partner (You can have two commanders if both have partner.)

Gimli, Counter of Kills

Trample
Whenever a creature an opponent controls dies, Gimli, Counter of Kills deals 1 damage to that creature's controller.

Akoum Refuge

Akoum Refuge enters tapped.
When Akoum Refuge enters, you gain 1 life.
{T}: Add {B} or {R}.

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.

Obosh, the Preypiercer

Companion — Your starting deck contains only cards with odd mana values and land cards. (If this card is your chosen companion, you may put it into your hand from outside the game for {3} as a sorcery.)
If a source you control with an odd mana value would deal damage to a permanent or player, it deals double that damage to that permanent or player instead.

Witty Roastmaster

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

Perpetual Timepiece

{T}: Mill two cards.
{2}, Exile Perpetual Timepiece: Shuffle any number of target cards from your graveyard into your library.

Molten Birth

Create two 1/1 red Elemental creature tokens, then flip a coin. If you win the flip, return Molten Birth to its owner's hand.

Lightning Axe

As an additional cost to cast this spell, discard a card or pay {5}.
Lightning Axe deals 5 damage to target creature.

Tectonic Hazard

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

Abrade

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

Path of Ancestry

Path of Ancestry 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.)

Lightning Strike

Lightning Strike deals 3 damage to any target.

Impact Tremors

Whenever a creature you control enters, this enchantment deals 1 damage to each opponent.

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.

Blazing Volley

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

Sol Ring

Iron-Fist Pulverizer

Reach
Whenever you cast your second spell each turn, Iron-Fist Pulverizer deals 2 damage to target opponent. Scry 1. (Look at the top card of your library. You may put that card on the bottom.)

Smoldering Marsh

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

Unruly Catapult

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

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."

Molten Gatekeeper

Whenever another creature you control enters, Molten Gatekeeper 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.)

Victimize

Choose two target creature cards in your graveyard. Sacrifice a creature. If you do, return the chosen cards to the battlefield tapped.

Captain Ripley Vance

Whenever you cast your third spell each turn, put a +1/+1 counter on Captain Ripley Vance, then it deals damage equal to its power to any target.

Mountain

Tunneling Geopede

Landfall — Whenever a land you control enters, Tunneling Geopede deals 1 damage to each opponent.

Deadly Rollick

If you control a commander, you may cast this spell without paying its mana cost.
Exile target creature.

Goblin Rally

Create four 1/1 red Goblin creature tokens.

Spitfire Lagac

Landfall — Whenever a land you control enters, this creature deals 1 damage to each opponent.

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.

Exotic Orchard

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

Arcane Signet

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

Relic Amulet

Whenever you cast an instant, sorcery, or Wizard spell, put a charge counter on Relic Amulet.
{2}, {T}, Remove all charge counters from Relic Amulet: It deals that much damage to target creature.

Chandra's Fury

Chandra's Fury deals 4 damage to target player or planeswalker and 1 damage to each creature that player or that planeswalker's controller controls.

Commander's Sphere

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

Garna, Bloodfist of Keld

Whenever another creature you control dies, draw a card if it was attacking. Otherwise, Garna deals 1 damage to each opponent.

Raise Dead

Return target creature card from your graveyard to your hand.

Kazuul, Tyrant of the Cliffs

Whenever a creature an opponent controls attacks, if you're the defending player, create a 3/3 red Ogre creature token unless that creature's controller pays {3}.

Agate Assault

Choose one —
• Agate Assault deals 4 damage to target creature. If that creature would die this turn, exile it instead.
• Exile target artifact.

Pyre Hound

Trample
Whenever you cast an instant or sorcery spell, put a +1/+1 counter on Pyre Hound.

Cast into the Fire

Choose one —
• Cast into the Fire deals 1 damage to each of up to two target creatures.
• Exile target artifact.

Cast Down

Leyline of Combustion

If Leyline of Combustion is in your opening hand, you may begin the game with it on the battlefield.
Whenever you and/or at least one permanent you control becomes the target of a spell or ability an opponent controls, Leyline of Combustion deals 2 damage to that player.

Judith, the Scourge Diva

Other creatures you control get +1/+0.
Whenever a nontoken creature you control dies, Judith, the Scourge Diva deals 1 damage to any target.

Demand Answers

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

Disciples of the Inferno

Prowess (Whenever you cast a noncreature spell, this creature gets +1/+1 until end of turn.)
If a noncreature source you control would deal damage to a creature, battle, or opponent, it deals that much damage plus 2 instead.

Invasion of Regatha

(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 Regatha enters, it deals 4 damage to another target battle or opponent and 1 damage to up to one target creature.

Invasion of Regatha // Disciples of the Inferno

Gibbering Fiend

When Gibbering Fiend enters, it deals 1 damage to each opponent.
Delirium — At the beginning of each opponent's upkeep, if there are four or more card types among cards in your graveyard, Gibbering Fiend deals 1 damage to that player.

Frantic Firebolt

Frantic Firebolt deals X damage to target creature, where X is 2 plus the number of cards in your graveyard that are instant cards, sorcery cards, and/or have an Adventure.

Breath of Malfegor

Breath of Malfegor deals 5 damage to each opponent.

Symmetry Matrix

Whenever a creature you control with power equal to its toughness enters, you may pay {1}. If you do, draw a card.

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 the Younger deals 2 damage to any target.

Mirkwood Bats

Flying
Whenever you create or sacrifice a token, each opponent loses 1 life.

Tainted Peak

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

Spellgorger Weird

Whenever you cast a noncreature spell, put a +1/+1 counter on Spellgorger Weird.

Spell Satchel

Magecraft — Whenever you cast or copy an instant or sorcery spell, put a book counter on Spell Satchel.
{T}, Remove a book counter from Spell Satchel: Add {C}.
{3}, {T}, Remove three book counters from Spell Satchel: Draw a card.

Swamp

Force of Rage

If it's not your turn, you may exile a red card from your hand rather than pay this spell's mana cost.
Create two 3/1 red Elemental creature tokens with trample and haste. Sacrifice those tokens at the beginning of your next upkeep.

Dragon Fodder

Create two 1/1 red Goblin creature tokens.

Fiery Impulse

Fiery Impulse deals 2 damage to target creature.
Spell mastery — If there are two or more instant and/or sorcery cards in your graveyard, Fiery Impulse deals 3 damage instead.

Thermo-Alchemist

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

Back for Seconds

Bargain (You may sacrifice an artifact, enchantment, or token as you cast this spell.)
Return up to two target creature cards from your graveyard to your hand. If this spell was bargained, you may put one of those cards with mana value 4 or less onto the battlefield instead of putting it into your hand.

Fiery Inscription

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

Flame Slash

Flame Slash deals 4 damage to target creature.

Command Tower

This spell can't be countered.
Fry deals 5 damage to target creature or planeswalker that's white or blue.