Manabarbs

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

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.

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.

Magus of the Wheel

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

Sol Ring

Underworld Fires

Underworld Fires deals 1 damage to each creature and each planeswalker. If a permanent dealt damage this way would die this turn, exile it instead.

Earthquake

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

Wayfarer's Bauble

{2}, {T}, Sacrifice Wayfarer's Bauble: Search your library for a basic land card, put that card onto the battlefield tapped, then shuffle.

Arcane Signet

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

Curse of Opulence

Enchant player
Whenever enchanted player is attacked, create a Gold token. Each opponent attacking that player does the same. (A Gold token is an artifact with "Sacrifice this artifact: Add one mana of any color.")

Zo-Zu the Punisher

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

Shenanigans

Destroy target artifact.
Dredge 1 (If you would draw a card, you may mill a card instead. If you do, return this card from your graveyard to your hand.)

Nykthos, Shrine to Nyx

{T}: Add {C}.
{2}, {T}: Choose a color. Add an amount of mana of that color equal to your devotion to that color. (Your devotion to a color is the number of mana symbols of that color in the mana costs of permanents you control.)

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.

Dualcaster Mage

Flash
When Dualcaster Mage enters the battlefield, copy target instant or sorcery spell. You may choose new targets for the copy.

Goblin Chainwhirler

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

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.

Pyrostatic Pillar

Whenever a player casts a spell with mana value 3 or less, Pyrostatic Pillar deals 2 damage to that player.

Ruby Medallion

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

Darksteel Plate

Indestructible
Equipped creature has indestructible.
Equip {2}

Slagstorm

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

Flamekin Village

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

Endless Atlas

{2}, {T}: Draw a card. Activate only if you control three or more lands with the same name.

Glint-Horn Buccaneer

Haste
Whenever you discard a card, Glint-Horn Buccaneer deals 1 damage to each opponent.
{1}{R}, Discard a card: Draw a card. Activate only if Glint-Horn Buccaneer is attacking.

Cunning Sparkmage

Haste
{T}: Cunning Sparkmage deals 1 damage to any target.

Volcanic Fallout

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

Neheb, Dreadhorde Champion

Trample
Whenever Neheb, Dreadhorde Champion deals combat damage to a player or planeswalker, you may discard any number of cards. If you do, draw that many cards and add that much {R}. Until end of turn, you don't lose this mana as steps and phases end.

Rampaging Ferocidon

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

Pyroclasm

Pyroclasm deals 2 damage to each creature.

Guttersnipe

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

Tilonalli's Summoner

Ascend (If you control ten or more permanents, you get the city's blessing for the rest of the game.)
Whenever Tilonalli's Summoner attacks, you may pay {X}{R}. If you do, create X 1/1 red Elemental creature tokens that are tapped and attacking. At the beginning of the next end step, exile those tokens unless you have the city's blessing.

Thrill of Possibility

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

Flame Jab

Flame Jab deals 1 damage to any target.
Retrace (You may cast this card from your graveyard by discarding a land card in addition to paying its other costs.)

Reverberate

Copy target instant or sorcery spell. You may choose new targets for the copy.

Seismic Assault

Discard a land card: Seismic Assault deals 2 damage to any target.

Swiftfoot Boots

Equipped creature has hexproof and haste. (It can't be the target of spells or abilities your opponents control.)
Equip {1}

Fire Diamond

Fire Diamond enters the battlefield tapped.
{T}: Add {R}.

Barrage of Boulders

Barrage of Boulders deals 1 damage to each creature you don't control.
Ferocious — If you control a creature with power 4 or greater, creatures can't block this turn.

Mountain

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.

Slice and Dice

Slice and Dice deals 4 damage to each creature.
Cycling {2}{R} ({2}{R}, Discard this card: Draw a card.)
When you cycle Slice and Dice, you may have it deal 1 damage to each creature.

Deflecting Swat

If you control a commander, you may cast this spell without paying its mana cost.
You may choose new targets for target spell or ability.

Thermo-Alchemist

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

Anger

Haste
As long as Anger is in your graveyard and you control a Mountain, creatures you control have haste.

Young Pyromancer

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

Purphoros, God of the Forge

Indestructible
As long as your devotion to red is less than five, Purphoros isn't a creature.
Whenever another creature enters the battlefield under your control, Purphoros deals 2 damage to each opponent.
{2}{R}: Creatures you control get +1/+0 until end of turn.

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.)

Hissing Iguanar

Whenever another creature dies, you may have Hissing Iguanar deal 1 damage to target player or planeswalker.

Eidolon of the Great Revel

Whenever a player casts a spell with mana value 3 or less, Eidolon of the Great Revel deals 2 damage to that player.

Spear Spewer

Defender
{T}: Spear Spewer deals 1 damage to each player.

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.

Lightning Greaves

Equipped creature has haste and shroud. (It can't be the target of spells or abilities.)
Equip {0}

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.

Starstorm

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

Price of Progress

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

Chandra, Fire Artisan

Whenever one or more loyalty counters are removed from Chandra, Fire Artisan, she deals that much damage to target opponent or planeswalker.
+1: Exile the top card of your library. You may play it this turn.
−7: Exile the top seven cards of your library. You may play them this turn.

Scab-Clan Berserker

Haste
Renown 1 (When this creature deals combat damage to a player, if it isn't renowned, put a +1/+1 counter on it and it becomes renowned.)
Whenever an opponent casts a noncreature spell, if Scab-Clan Berserker is renowned, Scab-Clan Berserker deals 2 damage to that player.

Goblin Sharpshooter

Goblin Sharpshooter doesn't untap during your untap step.
Whenever a creature dies, untap Goblin Sharpshooter.
{T}: Goblin Sharpshooter deals 1 damage to any target.

Impact Tremors

Whenever a creature enters the battlefield under your control, Impact Tremors deals 1 damage to each opponent.

Anje's Ravager

Anje's Ravager attacks each combat if able.
Whenever Anje's Ravager attacks, discard your hand, then draw three cards.
Madness {1}{R} (If you discard this card, discard it into exile. When you do, cast it for its madness cost or put it into your graveyard.)

Firebrand Archer

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

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."

Blood Moon

Electrostatic Field

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

Solemn Simulacrum

When Solemn Simulacrum enters the battlefield, 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.

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.")