Cosi's Ravager

Landfall — Whenever a land you control enters, you may have Cosi's Ravager deal 1 damage to target player or planeswalker.

Barrel Down Sokenzan

Sweep — Return any number of Mountains you control to their owner's hand. Barrel Down Sokenzan deals damage to target creature equal to twice the number of Mountains returned this way.

Mogg Maniac

Whenever Mogg Maniac is dealt damage, it deals that much damage to target opponent or planeswalker.

Chain Reaction

Chain Reaction deals X damage to each creature, where X is the number of creatures on the battlefield.

Oxidda Golem

Affinity for Mountains (This spell costs {1} less to cast for each Mountain you control.)
Haste

Pilgrim's Eye

Flying
When Pilgrim's Eye enters, you may search your library for a basic land card, reveal it, put it into your hand, then shuffle.

Starstorm

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

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.

Granite Grip

Enchant creature
Enchanted creature gets +1/+0 for each Mountain you control.

Journeyer's Kite

{3}, {T}: Search your library for a basic land card, reveal it, put it into your hand, then shuffle.

Fireball

This spell costs {1} more to cast for each target beyond the first.
Fireball deals X damage divided evenly, rounded down, among any number of targets.

Spawn of Thraxes

Flying
When Spawn of Thraxes enters, it deals damage to any target equal to the number of Mountains you control.

Dragonmaster Outcast

At the beginning of your upkeep, if you control six or more lands, create a 5/5 red Dragon creature token with flying.

Ben-Ben, Akki Hermit

{T}: Ben-Ben, Akki Hermit deals damage to target attacking creature equal to the number of untapped Mountains you control.

Burnished Hart

{3}, Sacrifice Burnished Hart: Search your library for up to two basic land cards, put them onto the battlefield tapped, then shuffle.

Goblin Diplomats

{T}: Each creature attacks this turn if able.

Fire Diamond

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

Purphoros's Intervention

Choose one —
• Create an X/1 red Elemental creature token with trample and haste. Sacrifice it at the beginning of the next end step.
• Purphoros's Intervention deals twice X damage to target creature or planeswalker.

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.)

Claws of Valakut

Enchant creature
Enchanted creature gets +1/+0 for each Mountain you control and has first strike.

Armillary Sphere

{2}, {T}, Sacrifice Armillary Sphere: Search your library for up to two basic land cards, reveal them, put them into your hand, then shuffle.

Dragon's Claw

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

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.

Staff of the Flame Magus

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

Hedron Archive

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

Dormant Volcano

Dormant Volcano enters tapped.
When Dormant Volcano enters, sacrifice it unless you return an untapped Mountain you control to its owner's hand.
{T}: Add {C}{R}.

Banefire

Banefire deals X damage to any target.
If X is 5 or more, this spell can't be countered and the damage can't be prevented.

Fumiko the Lowblood

Fumiko the Lowblood has bushido X, where X is the number of attacking creatures. (Whenever this creature blocks or becomes blocked, it gets +X/+X until end of turn.)
Creatures your opponents control attack each combat if able.

Curse of the Nightly Hunt

Enchant player
Creatures enchanted player controls attack each combat if able.

Pyromancer's Goggles

{T}: Add {R}. When that mana is spent to cast a red instant or sorcery spell, copy that spell and you may choose new targets for the copy.

Thrill of Possibility

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

Reiterate

Buyback {3} (You may pay an additional {3} as you cast this spell. If you do, put this card into your hand as it resolves.)
Copy target instant or sorcery spell. You may choose new targets for the copy.

Seismic Strike

Seismic Strike deals damage to target creature equal to the number of Mountains you control.

Akoum Hellkite

Flying
Landfall — Whenever a land you control enters, Akoum Hellkite deals 1 damage to any target. If that land is a Mountain, Akoum Hellkite deals 2 damage instead.

Mikokoro, Center of the Sea

{T}: Add {C}.
{2}, {T}: Each player draws a card.

Magus of the Wheel

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

Spire Barrage

Spire Barrage deals damage to any target equal to the number of Mountains you control.

Tunneling Geopede

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

Awaken the Ancient

Enchant Mountain
Enchanted Mountain is a 7/7 red Giant creature with haste. It's still a land.

Obsidian Fireheart

{1}{R}{R}: Put a blaze counter on target land without a blaze counter on it. For as long as that land has a blaze counter on it, it has "At the beginning of your upkeep, this land deals 1 damage to you." (The land continues to burn after Obsidian Fireheart has left the battlefield.)

Burning Earth

Whenever a player taps a nonbasic land for mana, Burning Earth deals 1 damage to that player.

Tibalt, Rakish Instigator

Your opponents can't gain life.
−2: Create a 1/1 red Devil creature token with "When this creature dies, it deals 1 damage to any target."

Myriad Landscape

Myriad Landscape enters tapped.
{T}: Add {C}.
{2}, {T}, Sacrifice Myriad Landscape: Search your library for up to two basic land cards that share a land type, put them onto the battlefield tapped, then shuffle.

Heraldic Banner

As Heraldic Banner enters, choose a color.
Creatures you control of the chosen color get +1/+0.
{T}: Add one mana of the chosen color.

Coalhauler Swine

Whenever Coalhauler Swine is dealt damage, it deals that much damage to each player.

Wild Ricochet

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

Tibalt's Trickery

Counter target spell. Choose 1, 2, or 3 at random. Its controller mills that many cards, then exiles cards from the top of their library until they exile a nonland card with a different name than that spell. They may cast that card without paying its mana cost. Then they put the exiled cards on the bottom of their library in a random order.

Temple of the False God

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

Cathartic Reunion

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

Combustible Gearhulk

First strike
When Combustible Gearhulk enters, target opponent may have you draw three cards. If the player doesn't, you mill three cards, then Combustible Gearhulk deals damage to that player equal to the total mana value of those cards.

Arcbond

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

Jaws of Stone

Jaws of Stone deals X damage divided as you choose among any number of targets, where X is the number of Mountains you control as you cast this spell.

Mountain

Ghirapur Orrery

Each player may play an additional land on each of their turns.
At the beginning of each player's upkeep, if that player has no cards in hand, that player draws three cards.

Commander's Sphere

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

Pendant of Prosperity

Pendant of Prosperity enters under the control of an opponent of your choice.
{2}, {T}: Draw a card, then you may put a land card from your hand onto the battlefield. Pendant of Prosperity's owner draws a card, then that player may put a land card from their hand onto the battlefield.

Prismatic Lens

{T}: Add {C}.
{1}, {T}: Add one mana of any color.

Downhill Charge

You may sacrifice a Mountain rather than pay this spell's mana cost.
Target creature gets +X/+0 until end of turn, where X is the number of Mountains you control.

Fall of the Titans

Surge {X}{R} (You may cast this spell for its surge cost if you or a teammate has cast another spell this turn.)
Fall of the Titans deals X damage to each of up to two targets.

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.

Rage Nimbus

Defender, flying
{1}{R}: Target creature attacks this turn if able.

Walking Atlas

{T}: You may put a land card from your hand onto the battlefield.

Spitting Earth

Spitting Earth deals damage to target creature equal to the number of Mountains you control.

Mind Stone

{T}: Add {C}.
{1}, {T}, Sacrifice Mind Stone: Draw a card.

Kazuul, Tyrant of the Cliffs

Whenever a creature an opponent controls attacks, if you're the defending player, create a 3/3 red Ogre creature token unless that creature's controller pays {3}.

Arch of Orazca

Ascend (If you control ten or more permanents, you get the city's blessing for the rest of the game.)
{T}: Add {C}.
{5}, {T}: Draw a card. Activate only if you have the city's blessing.