Fault Line

Fault Line deals X damage to each creature without flying and each player.

Spear Spewer

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

Hungry Flames

Hungry Flames deals 3 damage to target creature and 2 damage to target player or planeswalker.

Volcano Hellion

This creature has echo {X}, where X is your life total. (At the beginning of your upkeep, if this came under your control since the beginning of your last upkeep, sacrifice it unless you pay its echo cost.)
When this creature enters, it deals an amount of damage of your choice to you and target creature. The damage can't be prevented.

Heartless Hidetsugu

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

City of Brass

Whenever this land becomes tapped, it deals 1 damage to you.
{T}: Add one mana of any color.

Cave-In

You may exile a red card from your hand rather than pay this spell's mana cost.
Cave-In deals 2 damage to each creature and each player.

Fire Tempest

Fire Tempest deals 6 damage to each creature and each player.

The Fire Crystal

Red spells you cast cost {1} less to cast.
Creatures you control have haste.
{4}{R}{R}, {T}: Create a token that's a copy of target creature you control. Sacrifice it at the beginning of the next end step.

Probably Cut

Kookus

Trample
At the beginning of your upkeep, if you don't control a creature named Keeper of Kookus, this creature deals 3 damage to you and attacks this turn if able.
{R}: This creature gets +1/+0 until end of turn.

Molten Disaster

Kicker {R} (You may pay an additional {R} as you cast this spell.)
If this spell was kicked, it has split second. (As long as this spell is on the stack, players can't cast spells or activate abilities that aren't mana abilities.)
Molten Disaster deals X damage to each creature without flying and each player.

Rolling Earthquake

Rolling Earthquake deals X damage to each creature without horsemanship and each player.

Ian the Reckless

Whenever Ian the Reckless attacks, if it's modified, you may have it deal damage equal to its power to you and any target. (Equipment, Auras you control, and counters are modifications.)

Staff of the Flame Magus

Whenever you cast a red spell or a Mountain you control enters, you gain 1 life.

Torture Chamber

At the beginning of your upkeep, put a pain counter on this artifact.
At the beginning of your end step, this artifact deals damage to you equal to the number of pain counters on it.
{1}, {T}, Remove all pain counters from this artifact: It deals damage to target creature equal to the number of pain counters removed this way.

Warmonger

{2}: This creature deals 1 damage to each creature without flying and each player. Any player may activate this ability.

Exocrine

Ravenous (This creature enters with X +1/+1 counters on it. If X is 5 or more, draw a card when it enters.)
Bio-plasmic Barrage — When this creature enters, it deals X damage to each player and each other creature.

Magma Phoenix

Flying
When this creature dies, it deals 3 damage to each creature and each player.
{3}{R}{R}: Return this card from your graveyard to your hand.

Coalhauler Swine

Whenever this creature is dealt damage, it deals that much damage to each player.

Auntie Blyte, Bad Influence

Flying
Whenever a source you control deals damage to you, put that many +1/+1 counters on Auntie Blyte.
{1}{R}, {T}, Remove X +1/+1 counters from Auntie Blyte: It deals X damage to any target.

Slagstorm

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

Fires of Mount Doom

When Fires of Mount Doom enters, it deals 2 damage to target creature an opponent controls. Destroy all Equipment attached to that creature.
{2}{R}: Exile the top card of your library. You may play that card this turn. When you play a card this way, Fires of Mount Doom deals 2 damage to each player.

Ruby Medallion

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

Earthquake

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

Barbarian Ring

{T}: Add {R}. This land deals 1 damage to you.
Threshold — {R}, {T}, Sacrifice this land: It deals 2 damage to any target. Activate only if seven or more cards are in your graveyard.

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.

Platinum Angel

Flying
You can't lose the game and your opponents can't win the game.

Goldnight Castigator

Flying, haste
If a source would deal damage to you, it deals double that damage to you instead.
If a source would deal damage to this creature, it deals double that damage to this creature instead.

Grand Coliseum

This land enters tapped.
{T}: Add {C}.
{T}: Add one mana of any color. This land deals 1 damage to you.

Orcish Cannonade

Orcish Cannonade deals 2 damage to any target and 3 damage to you.
Draw a card.

Adventurer's Inn

When this land enters, you gain 2 life.
{T}: Add {C}.

Sulfurous Blast

Sulfurous Blast deals 2 damage to each creature and each player. If you cast this spell during your main phase, Sulfurous Blast deals 3 damage to each creature and each player instead.

Incite Rebellion

For each player, Incite Rebellion deals damage to that player and each creature that player controls equal to the number of creatures they control.

Blockbuster

{1}{R}, Sacrifice this enchantment: It deals 3 damage to each tapped creature and each player.

Witch's Clinic

{T}: Add {C}.
{2}, {T}: Target commander gains lifelink until end of turn.

Magma Giant

When this creature enters, it deals 2 damage to each creature and each player.

Mountain

Trenchpost

{T}: Add {C}.
{3}, {T}: Target player mills a card for each Locus you control.

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.

Steam Blast

Steam Blast deals 2 damage to each creature and each player.

Hammerfist Giant

{T}: This creature deals 4 damage to each creature without flying and each player.

Arcbond

Choose target creature. Whenever that creature is dealt damage this turn, it deals that much damage to each other creature and each player.

Ancient Tomb

{T}: Add {C}{C}. This land deals 2 damage to you.

Cloudpost

This land enters tapped.
{T}: Add {C} for each Locus on the battlefield.

Radiant Fountain

Menacing Ogre

Trample, haste
When this creature enters, each player secretly chooses a number. Then those numbers are revealed. Each player with the highest number loses that much life. If you are one of those players, put two +1/+1 counters on this creature.

Planar Nexus

This land is every nonbasic land type. (Nonbasic land types include Cave, Desert, Gate, Lair, Locus, Mine, Power-Plant, Sphere, Tower, and Urza's.)
{T}: Add {C}.
{1}, {T}: Add one mana of any color.

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}.

Volcanic Fallout

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

Arcane Signet

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

Oath of Mages

At the beginning of each player's upkeep, that player chooses target player who has more life than they do and is their opponent. The first player may have this enchantment deal 1 damage to the second player.

Jade Monolith

{1}: The next time a source of your choice would deal damage to target creature this turn, that source deals that damage to you instead.

Seraph Sanctuary

When this land enters, you gain 1 life.
Whenever an Angel you control enters, you gain 1 life.
{T}: Add {C}.

Mages' Contest

You and target spell's controller bid life. You start the bidding with a bid of 1. In turn order, each player may top the high bid. The bidding ends if the high bid stands. The high bidder loses life equal to the high bid. If you win the bidding, counter that spell.

Goblin Psychopath

Whenever this creature attacks or blocks, flip a coin. If you lose the flip, the next time it would deal combat damage this turn, it deals that damage to you instead.

Price of Progress

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

Volcanic Spray

Volcanic Spray deals 1 damage to each creature without flying and each player.
Flashback {1}{R} (You may cast this card from your graveyard for its flashback cost. Then exile it.)

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.

Dragon's Claw

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

Flame Rift

Flame Rift deals 4 damage to each player.

Batterbone

Living weapon (When this Equipment enters, create a 0/0 black Phyrexian Germ creature token, then attach this to it.)
Equipped creature gets +1/+1 and has vigilance and lifelink.
Equip {5}

Ashling the Pilgrim

{1}{R}: Put a +1/+1 counter on Ashling. If this is the third time this ability has resolved this turn, remove all +1/+1 counters from Ashling, and it deals that much damage to each creature and each player.

Whirling Catapult

{2}, Exile the top two cards of your library: This artifact deals 1 damage to each creature with flying and each player.

Rain of Embers

Rain of Embers deals 1 damage to each creature and each player.

Breath of Darigaaz

Kicker {2} (You may pay an additional {2} as you cast this spell.)
Breath of Darigaaz deals 1 damage to each creature without flying and each player. If this spell was kicked, it deals 4 damage to each creature without flying and each player instead.

Time Bomb

At the beginning of your upkeep, put a time counter on this artifact.
{1}, {T}, Sacrifice this artifact: This artifact deals damage equal to the number of time counters on it to each creature and each player.

Glimmerpost

When this land enters, you gain 1 life for each Locus on the battlefield.
{T}: Add {C}.

Batterskull

Living weapon (When this Equipment enters, create a 0/0 black Phyrexian Germ creature token, then attach this to it.)
Equipped creature gets +4/+4 and has vigilance and lifelink.
{3}: Return this Equipment to its owner's hand.
Equip {5}

Themberchaud

Trample
When Themberchaud enters, he deals X damage to each other creature without flying and each player, where X is the number of Mountains you control.
You may exert Themberchaud as he attacks. When you do, he gains flying until end of turn. (An exerted creature won't untap during your next untap step.)

Delete

Delete deals X damage to each nonartifact creature and each player.

Madcap Experiment

Reveal cards from the top of your library until you reveal an artifact card. Put that card onto the battlefield and the rest on the bottom of your library in a random order. Madcap Experiment deals damage to you equal to the number of cards revealed this way.

Inferno

Inferno deals 6 damage to each creature and each player.

Flamebreak

Flamebreak deals 3 damage to each creature without flying and each player. Creatures dealt damage this way can't be regenerated this turn.

Armageddon Clock

At the beginning of your upkeep, put a doom counter on this artifact.
At the beginning of your draw step, this artifact deals damage equal to the number of doom counters on it to each player.
{4}: Remove a doom counter from this artifact. Any player may activate this ability but only during any upkeep step.