Breath of Malfegor

Breath of Malfegor deals 5 damage to each opponent.

Dark Ritual

Viridian Longbow

Equipped creature has "{T}: This creature deals 1 damage to any target."
Equip {3} ({3}: Attach to target creature you control. Equip only as a sorcery. This card enters unattached and stays on the battlefield if the creature leaves.)

Read the Bones

Scry 2, then draw two cards. You lose 2 life. (To scry 2, look at the top two cards of your library, then put any number of them on the bottom and the rest on top in any order.)

Temple of the False God

{T}: Add {C}{C}. Activate only if you control five or more lands.

Kamahl, Pit Fighter

Haste (This creature can attack and {T} as soon as it comes under your control.)
{T}: Kamahl, Pit Fighter deals 3 damage to any target.

Embermaw Hellion

Trample (This creature can deal excess combat damage to the player or planeswalker it's attacking.)
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.

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.

Lightning Reaver

Haste; fear (This creature can't be blocked except by artifact creatures and/or black creatures.)
Whenever Lightning Reaver deals combat damage to a player, put a charge counter on it.
At the beginning of your end step, Lightning Reaver deals damage equal to the number of charge counters on it to each opponent.

Swiftfoot Boots

Equipped creature has hexproof and haste. (It can't be the target of spells or abilities your opponents control. It can attack and {T} no matter when it came under your control.)
Equip {1} ({1}: Attach to target creature you control. Equip only as a sorcery.)

Mana Clash

You and target opponent each flip a coin. Mana Clash deals 1 damage to each player whose coin comes up tails. Repeat this process until both players' coins come up heads on the same flip.

Goblin Fireslinger

{T}: Goblin Fireslinger deals 1 damage to target player or planeswalker.

Heartless Hidetsugu

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

Underworld Dreams

Whenever an opponent draws a card, Underworld Dreams deals 1 damage to that player.

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.

Browbeat

Any player may have Browbeat deal 5 damage to them. If no one does, target player draws three cards.

Spellshock

Whenever a player casts a spell, Spellshock deals 2 damage to that player.

Cerebral Eruption

Target opponent reveals the top card of their library. Cerebral Eruption deals damage equal to the revealed card's mana value to that player and each creature that player controls. If a land card is revealed this way, return Cerebral Eruption to its owner's hand.

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.")

Cinder Pyromancer

{T}: Cinder Pyromancer deals 1 damage to target player or planeswalker.
Whenever you cast a red spell, you may untap Cinder Pyromancer.

Sizzle

Firebrand Archer

Whenever you cast a noncreature spell, this creature deals 1 damage to each opponent.

Pyromancer's Gauntlet

If a red instant or sorcery spell you control or a red planeswalker you control would deal damage to a permanent or player, it deals that much damage plus 2 to that permanent or player instead.

Spiteful Visions

At the beginning of each player's draw step, that player draws an additional card.
Whenever a player draws a card, Spiteful Visions deals 1 damage to that player.

Cunning Sparkmage

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

Seething Song

Sign in Blood

Target player draws two cards and loses 2 life.

Blood Cultist

{T}: Blood Cultist deals 1 damage to target creature.
Whenever a creature dealt damage by Blood Cultist this turn dies, put a +1/+1 counter on Blood Cultist.

Vithian Stinger

{T}: Vithian Stinger deals 1 damage to any target.
Unearth {1}{R} ({1}{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.)

Toralf's Hammer

Equipped creature has "{1}{R}, {T}, Unattach Toralf's Hammer: It deals 3 damage to any target. Return Toralf's Hammer to its owner's hand."
Equipped creature gets +3/+0 as long as it's legendary.
Equip {1}{R}

Toralf, God of Fury

Trample
Whenever a creature or planeswalker an opponent controls is dealt excess noncombat damage, Toralf deals damage equal to the excess to any target other than that permanent.

Toralf, God of Fury // Toralf's Hammer

Kederekt Parasite

Whenever an opponent draws a card, if you control a red permanent, you may have Kederekt Parasite deal 1 damage to that player.

Chandra, Roaring Flame

+1: Chandra, Roaring Flame deals 2 damage to target player or planeswalker.
−2: Chandra, Roaring Flame deals 2 damage to target creature.
−7: Chandra, Roaring Flame deals 6 damage to each opponent. Each player dealt damage this way gets an emblem with "At the beginning of your upkeep, this emblem deals 3 damage to you."

Chandra, Fire of Kaladesh

Whenever you cast a red spell, untap Chandra, Fire of Kaladesh.
{T}: Chandra, Fire of Kaladesh deals 1 damage to target player or planeswalker. If Chandra has dealt 3 or more damage this turn, exile her, then return her to the battlefield transformed under her owner's control.

Chandra, Fire of Kaladesh // Chandra, Roaring Flame

Pestilent Spirit

Menace, deathtouch
Instant and sorcery spells you control have deathtouch. (Any amount of damage they deal to a creature is enough to destroy it.)

Sunscorched Desert

When Sunscorched Desert enters, it deals 1 damage to target player or planeswalker.
{T}: Add {C}.

Stuffy Doll

Indestructible
As Stuffy Doll enters, choose a player.
Whenever Stuffy Doll is dealt damage, it deals that much damage to the chosen player.
{T}: Stuffy Doll deals 1 damage to itself.

Blazing Volley

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

Syr Carah, the Bold

Whenever Syr Carah, the Bold or an instant or sorcery spell you control deals damage to a player, exile the top card of your library. You may play that card this turn.
{T}: Syr Carah deals 1 damage to any target.

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.

Thermo-Alchemist

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

Dictate of the Twin Gods

Flash
If a source would deal damage to a permanent or player, it deals double that damage to that permanent or player instead.

Fire Diamond

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

Spear Spewer

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

Chandra's Magmutt

{T}: Chandra's Magmutt deals 1 damage to target player or planeswalker.

Shivan Gorge

{T}: Add {C}.
{2}{R}, {T}: Shivan Gorge deals 1 damage to each opponent.

Syphon Mind

Each other player discards a card. You draw a card for each card discarded this way.

Sulfuric Vapors

If a red spell would deal damage to a permanent or player, it deals that much damage plus 1 to that permanent or player instead.

Zo-Zu the Punisher

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

Blood Pact

Terminate

Destroy target creature. It can't be regenerated.

Tunneling Geopede

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

Keldon Megaliths

Keldon Megaliths enters tapped.
{T}: Add {R}.
Hellbent — {1}{R}, {T}: Keldon Megaliths deals 1 damage to any target. Activate only if you have no cards in hand.

Lobber Crew

Defender
{T}: Lobber Crew deals 1 damage to each opponent.
Whenever you cast a multicolored spell, untap Lobber Crew.

Bedevil

Destroy target artifact, creature, or planeswalker.

Ill-Gotten Inheritance

At the beginning of your upkeep, Ill-Gotten Inheritance deals 1 damage to each opponent and you gain 1 life.
{5}{B}, Sacrifice Ill-Gotten Inheritance: It deals 4 damage to target opponent and you gain 4 life.

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.

Swamp

Vicious Rumors

Vicious Rumors deals 1 damage to each opponent. Each opponent discards a card, then mills a card. You gain 1 life.

Electrostatic Field

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

Manabarbs

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

Rakdos Signet

Charcoal Diamond

Charcoal Diamond enters tapped.
{T}: Add {B}.

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.

Guttersnipe

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

Skullcage

At the beginning of each opponent's upkeep, Skullcage deals 2 damage to that player unless they have exactly three or exactly four cards in hand.

Fate Unraveler

Whenever an opponent draws a card, Fate Unraveler deals 1 damage to that player.

Mountain

Fire Servant

If a red instant or sorcery spell you control would deal damage, it deals double that damage instead.

Commander's Sphere

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