Burn from Within

Burn from Within deals X damage to any target. If a creature is dealt damage this way, it loses indestructible until end of turn. If that creature would die this turn, exile it instead.

Chandra's Spitfire

Flying
Whenever an opponent is dealt noncombat damage, Chandra's Spitfire gets +3/+0 until end of turn.

Cinder Hellion

Trample
When Cinder Hellion enters, it deals 2 damage to target opponent or planeswalker.

Firecat Blitz

Create X 1/1 red Elemental Cat creature tokens with haste. Exile them at the beginning of the next end step.
Flashback—{R}{R}, Sacrifice X Mountains. (You may cast this card from your graveyard for its flashback cost. Then exile it.)

Mind Stone

{T}: Add {C}.
{1}, {T}, Sacrifice Mind Stone: Draw a card.

Desperate Ritual

Add {R}{R}{R}.
Splice onto Arcane {1}{R} (As you cast an Arcane spell, you may reveal this card from your hand and pay its splice cost. If you do, add this card's effects to that spell.)

Fanatical Firebrand

Haste
{T}, Sacrifice Fanatical Firebrand: It deals 1 damage to any target.

Blaze

Satyr Firedancer

Whenever an instant or sorcery spell you control deals damage to an opponent, Satyr Firedancer deals that much damage to target creature that player controls.

Young Pyromancer

Whenever you cast an instant or sorcery spell, create a 1/1 red Elemental creature token.

Flamekin Village

As Flamekin Village enters, you may reveal an Elemental card from your hand. If you don't, Flamekin Village enters tapped.
{T}: Add {R}.
{R}, {T}: Target creature gains haste until end of turn.

Sweltering Suns

Sweltering Suns deals 3 damage to each creature.
Cycling {3} ({3}, Discard this card: Draw a card.)

Chandra's Pyrohelix

Chandra's Pyrohelix deals 2 damage divided as you choose among one or two targets.

Firebrand Archer

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

Chandra's Embercat

{T}: Add {R}. Spend this mana only to cast an Elemental spell or a Chandra planeswalker spell.

Pyromancer's Assault

Whenever you cast your second spell each turn, Pyromancer's Assault deals 2 damage to any target.

Chandra, Torch of Defiance

+1: Exile the top card of your library. You may cast that card. If you don't, Chandra, Torch of Defiance deals 2 damage to each opponent.
+1: Add {R}{R}.
−3: Chandra, Torch of Defiance 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."

By Force

Soul's Fire

Target creature you control deals damage equal to its power to any target.

Generator Servant

{T}, Sacrifice Generator Servant: Add {C}{C}. If that mana is spent on a creature spell, it gains haste until end of turn. (That creature can attack and {T} as soon as it comes under your control.)

Forgotten Cave

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

Lightning Bolt

Lightning Bolt deals 3 damage to any target.

Chandra's Phoenix

Flying
Haste (This creature can attack and {T} as soon as it comes under your control.)
Whenever an opponent is dealt damage by a red instant or sorcery spell you control or by a red planeswalker you control, return Chandra's Phoenix from your graveyard to your hand.

Fireball

This spell costs {1} more to cast for each target beyond the first.
Fireball deals X damage divided evenly, rounded down, among any number of targets.

Burning Prophet

Whenever you cast a noncreature spell, Burning Prophet gets +1/+0 until end of turn, then scry 1.

Volt Charge

Volt Charge deals 3 damage to any target. Proliferate. (Choose any number of permanents and/or players, then give each another counter of each kind already there.)

Karplusan Hound

Whenever Karplusan Hound attacks, if you control a Chandra planeswalker, this creature deals 2 damage to any target.

Act on Impulse

Exile the top three cards of your library. Until end of turn, you may play those cards. (If you cast a spell this way, you still pay its costs. You can play a land this way only if you have an available land play remaining.)

Wildfire Elemental

Whenever an opponent is dealt noncombat damage, creatures you control get +1/+0 until end of turn.

Molten Vortex

{R}, Discard a land card: Molten Vortex deals 2 damage to any target.

Mountain

Thrill of Possibility

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

Ghitu Lavarunner

As long as there are two or more instant and/or sorcery cards in your graveyard, Ghitu Lavarunner gets +1/+0 and has haste.

Chandra's Regulator

Whenever you activate a loyalty ability of a Chandra planeswalker, you may pay {1}. If you do, copy that ability. You may choose new targets for the copy.
{1}, {T}, Discard a Mountain card or a red card: Draw a card.

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.

Pyretic Ritual

Scorch Spitter

Whenever Scorch Spitter attacks, it deals 1 damage to the player or planeswalker it's attacking.

Ravaging Blaze

Ravaging Blaze deals X damage to target creature.
Spell mastery — If there are two or more instant and/or sorcery cards in your graveyard, Ravaging Blaze also deals X damage to that creature's controller.

Chandra's Triumph

Chandra's Triumph deals 3 damage to target creature or planeswalker an opponent controls. Chandra's Triumph deals 5 damage instead if you control a Chandra planeswalker.

Hellion Crucible

{T}: Add {C}.
{1}{R}, {T}: Put a pressure counter on Hellion Crucible.
{1}{R}, {T}, Remove two pressure counters from Hellion Crucible and sacrifice it: Create a 4/4 red Hellion creature token with haste. (It can attack and {T} as soon as it comes under your control.)

Smash to Smithereens

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

Fire Urchin

Trample
Whenever you cast an instant or sorcery spell, Fire Urchin gets +1/+0 until end of turn.