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.

Spear Spewer

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

Flame Rift

Flame Rift deals 4 damage to each player.

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.

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.

Rain of Embers

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

Fire Tempest

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

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.)

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.

Flamebreak

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

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.

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.

Hammerfist Giant

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

Inferno

Inferno deals 6 damage to each creature and each player.

Earthquake

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

Devastate

Destroy target land. Devastate deals 1 damage to each creature and each player.

Blockbuster

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

Delete

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

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.

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.

Volcanic Fallout

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

Steam Blast

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

Rupture

Sacrifice a creature. Rupture deals damage equal to that creature's power to each creature without flying and each player.

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.

Coalhauler Swine

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

Acidic Soil

Acidic Soil deals damage to each player equal to the number of lands they control.

Magma Giant

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

Bloodfire Colossus

{R}, Sacrifice this creature: It deals 6 damage to each creature and each player.

Farideh's Fireball

Farideh's Fireball deals 5 damage to target creature or planeswalker. Roll a d20.
1—9 | Farideh's Fireball deals 2 damage to each player.
10—20 | Farideh's Fireball deals 2 damage to each opponent.

Rolling Earthquake

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

Slagstorm

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

Thunder of Hooves

Thunder of Hooves deals X damage to each creature without flying and each player, where X is the number of Beasts on the battlefield.

Heartless Hidetsugu

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

Fault Line

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

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.

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.