Outpost Siege

As Outpost Siege enters, choose Khans or Dragons.
• Khans — At the beginning of your upkeep, exile the top card of your library. Until end of turn, you may play that card.
• Dragons — Whenever a creature you control leaves the battlefield, Outpost Siege deals 1 damage to any target.

Vandalblast

Destroy target artifact you don't control.
Overload {4}{R} (You may cast this spell for its overload cost. If you do, change "target" in its text to "each.")

Ruby Medallion

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

Conjurer's Closet

At the beginning of your end step, you may exile target creature you control, then return that card to the battlefield under your control.

Shattering Spree

Replicate {R} (When you cast this spell, copy it for each time you paid its replicate cost. You may choose new targets for the copies.)
Destroy target artifact.

Caged Sun

As Caged Sun enters, choose a color.
Creatures you control of the chosen color get +1/+1.
Whenever a land's ability causes you to add one or more mana of the chosen color, add one additional mana of that color.

Altar of the Brood

Whenever another permanent you control enters, each opponent mills a card.

Panharmonicon

If an artifact or creature entering causes a triggered ability of a permanent you control to trigger, that ability triggers an additional time.

Experimental Frenzy

You may look at the top card of your library any time.
You may play lands and cast spells from the top of your library.
You can't play lands or cast spells from your hand.
{3}{R}: Destroy Experimental Frenzy.

Siege-Gang Commander

When Siege-Gang Commander enters, create three 1/1 red Goblin creature tokens.
{1}{R}, Sacrifice a Goblin: Siege-Gang Commander deals 2 damage to any target.

Pandemonium

Whenever a creature enters, that creature's controller may have it deal damage equal to its power to any target of their choice.

Tuktuk Scrapper

Whenever Tuktuk Scrapper or another Ally you control enters, you may destroy target artifact. If that artifact is put into a graveyard this way, Tuktuk Scrapper deals damage to that artifact's controller equal to the number of Allies you control.

Mask of Memory

Whenever equipped creature deals combat damage to a player, you may draw two cards. If you do, discard a card.
Equip {1} ({1}: Attach to target creature you control. Equip only as a sorcery.)

Grinning Ignus

{R}, Return Grinning Ignus to its owner's hand: Add {C}{C}{R}. Activate only as a sorcery.

Zealous Conscripts

Haste
When Zealous Conscripts enters, gain control of target permanent until end of turn. Untap that permanent. It gains haste until end of turn.

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.

Goblin Matron

When Goblin Matron enters, you may search your library for a Goblin card, reveal that card, put it into your hand, then shuffle.

Worn Powerstone

Worn Powerstone enters tapped.
{T}: Add {C}{C}.

Imperial Recruiter

When Imperial Recruiter enters, search your library for a creature card with power 2 or less, reveal it, put it into your hand, then shuffle.

Ancient Tomb

{T}: Add {C}{C}. Ancient Tomb deals 2 damage to you.

Sol Ring

Goblin Bombardment

Sacrifice a creature: Goblin Bombardment deals 1 damage to any target.

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.

Reforge the Soul

Each player discards their hand, then draws seven cards.
Miracle {1}{R} (You may cast this card for its miracle cost when you draw it if it's the first card you drew this turn.)

Mirror March

Whenever a nontoken creature you control enters, flip a coin until you lose a flip. For each flip you won, create a token that's a copy of that creature. Those tokens gain haste. Exile them at the beginning of the next end step.

Goblin Assault

At the beginning of your upkeep, create a 1/1 red Goblin creature token with haste.
Goblin creatures attack each combat if able.

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.

Blasphemous Act

This spell costs {1} less to cast for each creature on the battlefield.
Blasphemous Act deals 13 damage to each creature.

Abrade

Choose one —
• Abrade deals 3 damage to target creature.
• Destroy target artifact.

Runaway Steam-Kin

Whenever you cast a red spell, if Runaway Steam-Kin has fewer than three +1/+1 counters on it, put a +1/+1 counter on Runaway Steam-Kin.
Remove three +1/+1 counters from Runaway Steam-Kin: Add {R}{R}{R}.

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 you control enters, Purphoros deals 2 damage to each opponent.
{2}{R}: Creatures you control get +1/+0 until end of turn.

Krenko, Tin Street Kingpin

Whenever Krenko, Tin Street Kingpin attacks, put a +1/+1 counter on it, then create a number of 1/1 red Goblin creature tokens equal to Krenko's power.

Goblin Rabblemaster

Other Goblin creatures you control attack each combat if able.
At the beginning of combat on your turn, create a 1/1 red Goblin creature token with haste.
Whenever Goblin Rabblemaster attacks, it gets +1/+0 until end of turn for each other attacking Goblin.

Mind's Eye

Whenever an opponent draws a card, you may pay {1}. If you do, draw a card.

Tibalt, the Fiend-Blooded

+1: Draw a card, then discard a card at random.
−4: Tibalt, the Fiend-Blooded deals damage equal to the number of cards in target player's hand to that player.
−6: Gain control of all creatures until end of turn. Untap them. They gain haste until end of turn.

Mogg Infestation

Destroy all creatures target player controls. For each creature that died this way, that player creates two 1/1 red Goblin creature tokens.

Wasteland

{T}: Add {C}.
{T}, Sacrifice Wasteland: Destroy target nonbasic land.

Valakut, the Molten Pinnacle

Valakut, the Molten Pinnacle enters tapped.
Whenever a Mountain you control enters, if you control at least five other Mountains, you may have Valakut, the Molten Pinnacle deal 3 damage to any target.
{T}: Add {R}.

Koth of the Hammer

+1: Untap target Mountain. It becomes a 4/4 red Elemental creature until end of turn. It's still a land.
−2: Add {R} for each Mountain you control.
−5: You get an emblem with "Mountains you control have '{T}: This land deals 1 damage to any target.'"

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.

Confusion in the Ranks

Whenever an artifact, creature, or enchantment enters, its controller chooses target permanent another player controls that shares a card type with it. Exchange control of those permanents.

Norin the Wary

When a player casts a spell or a creature attacks, exile Norin the Wary. Return it to the battlefield under its owner's control at the beginning of the next end step.

Gauntlet of Power

As Gauntlet of Power enters, choose a color.
Creatures of the chosen color get +1/+1.
Whenever a basic land is tapped for mana of the chosen color, its controller adds an additional one mana of that color.

Skullclamp

Equipped creature gets +1/-1.
Whenever equipped creature dies, draw two cards.
Equip {1}

Magus of the Wheel

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

Pia and Kiran Nalaar

When Pia and Kiran Nalaar enters, create two 1/1 colorless Thopter artifact creature tokens with flying.
{2}{R}, Sacrifice an artifact: Pia and Kiran Nalaar deals 2 damage to any target.

Fire Diamond

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

Mountain

Skirk Prospector

Kiki-Jiki, Mirror Breaker

Haste
{T}: Create a token that's a copy of target nonlegendary creature you control, except it has haste. Sacrifice it at the beginning of the next end step.

Genesis Chamber

Whenever a nontoken creature enters, if Genesis Chamber is untapped, that creature's controller creates a 1/1 colorless Myr artifact creature token.

Wheel of Fate

Suspend 4—{1}{R} (Rather than cast this card from your hand, pay {1}{R} and exile it with four time counters on it. At the beginning of your upkeep, remove a time counter. When the last is removed, you may cast it without paying its mana cost.)
Each player discards their hand, then draws seven cards.

Chrome Mox

Imprint — When Chrome Mox enters, you may exile a nonartifact, nonland card from your hand.
{T}: Add one mana of any of the exiled card's colors.

Impact Tremors

Whenever a creature you control enters, Impact Tremors deals 1 damage to each opponent.

Strip Mine

{T}: Add {C}.
{T}, Sacrifice Strip Mine: Destroy target land.

Insurrection

Untap all creatures and gain control of them until end of turn. They gain haste until end of turn.

Warstorm Surge

Whenever a creature you control enters, it deals damage equal to its power to any target.

Treasonous Ogre

Dethrone (Whenever this creature attacks the player with the most life or tied for most life, put a +1/+1 counter on it.)
Pay 3 life: Add {R}.

Thran Dynamo

Solemn Simulacrum

When Solemn Simulacrum enters, 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.

Hedron Archive

{T}: Add {C}{C}.
{2}, {T}, Sacrifice Hedron Archive: Draw two cards.

Ghost Quarter

{T}: Add {C}.
{T}, Sacrifice Ghost Quarter: Destroy target land. Its controller may search their library for a basic land card, put it onto the battlefield, then shuffle.

Thought Vessel

You have no maximum hand size.
{T}: Add {C}.

Iron Myr

Neheb, the Eternal

Afflict 3 (Whenever this creature becomes blocked, defending player loses 3 life.)
At the beginning of your second main phase, add {R} for each 1 life your opponents have lost this turn.

Goblinslide

Whenever you cast a noncreature spell, you may pay {1}. If you do, create a 1/1 red Goblin creature token with haste.

Gamble

Search your library for a card, put that card into your hand, discard a card at random, then shuffle.

Ogre Battledriver

Whenever another creature you control enters, that creature gets +2/+0 and gains haste until end of turn. (It can attack and {T} this turn.)

Helm of the Host

At the beginning of combat on your turn, create a token that's a copy of equipped creature, except the token isn't legendary. That token gains haste.
Equip {5}