Spire Barrage

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

Fire Diamond

This artifact enters tapped.
{T}: Add {R}.

Comet Storm

Multikicker {1} (You may pay an additional {1} any number of times as you cast this spell.)
Choose any target, then choose another target for each time this spell was kicked. Comet Storm deals X damage to each of them.

Thrill of Possibility

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

Wild Guess

Ben-Ben, Akki Hermit

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

Magnetic Mountain

Blue creatures don't untap during their controllers' untap steps.
At the beginning of each player's upkeep, that player may choose any number of tapped blue creatures they control and pay {4} for each creature chosen this way. If the player does, untap those creatures.

Impact Resonance

Impact Resonance deals X damage divided as you choose among any number of target creatures, where X is the greatest amount of damage dealt by a source to a permanent or player this turn.

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.

Journeyer's Kite

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

Spitting Earth

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

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.

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.

Burnished Hart

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

Iron Myr

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.)

Howlpack Avenger

Whenever a permanent you control is dealt damage, this creature deals that much damage to any target.
{1}{R}: This creature gets +2/+0 until end of turn.
Nightbound (If a player casts at least two spells during their own turn, it becomes day next turn.)

Ill-Tempered Loner

Whenever this creature is dealt damage, it deals that much damage to any target.
{1}{R}: This creature gets +2/+0 until end of turn.
Daybound (If a player casts no spells during their own turn, it becomes night next turn.)

Ill-Tempered Loner // Howlpack Avenger

Spiteful Sliver

Sliver creatures you control have "Whenever this creature is dealt damage, it deals that much damage to target player or planeswalker."

Rumbling Rockslide

Rumbling Rockslide deals damage to target creature equal to the number of lands you control.

Akoum Hellkite

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

Staff of the Flame Magus

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

Myriad Landscape

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

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

Magmatic Insight

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

Cathartic Reunion

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

Gratuitous Violence

If a creature you control would deal damage to a permanent or player, it deals double that damage instead.

Recoup

Target sorcery card in your graveyard gains flashback until end of turn. The flashback cost is equal to its mana cost. (Mana cost includes color.)
Flashback {3}{R} (You may cast this card from your graveyard for its flashback cost. Then exile it.)

Coalhauler Swine

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

Brass's Bounty

For each land you control, create a Treasure token. (It's an artifact with "{T}, Sacrifice this token: Add one mana of any color.")

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.)

Boil

Walking Atlas

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

Pariah's Shield

All damage that would be dealt to you is dealt to equipped creature instead.
Equip {3}

Tormenting Voice

Seer's Sundial

Landfall — Whenever a land you control enters, you may pay {2}. If you do, draw a card.

Angrath's Marauders

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

Humble Defector

{T}: Draw two cards. Target opponent gains control of this creature. Activate only during your turn.

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.

Pendant of Prosperity

This artifact 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. This artifact's owner draws a card, then that player may put a land card from their hand onto the battlefield.

Seismic Strike

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

Goblin Diplomats

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

Dragon's Claw

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

Spawn of Thraxes

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

Claws of Valakut

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

Mana Geode

When this artifact enters, scry 1.
{T}: Add one mana of any color.

Fiendlash

Equipped creature gets +2/+0 and has reach.
Whenever equipped creature is dealt damage, it deals damage equal to its power to target player or planeswalker.
Equip {2}{R}

Scaretiller

Whenever this creature becomes tapped, choose one —
• You may put a land card from your hand onto the battlefield tapped.
• Return target land card from your graveyard to the battlefield tapped.

Mountain

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.'"

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.

Stuffy Doll

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

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.

Tectonic Reformation

Each land card in your hand has cycling {R}.
Cycling {2} ({2}, Discard this card: Draw a card.)

Invader Parasite

Imprint — When this creature enters, exile target land.
Whenever a land an opponent controls with the same name as the exiled card enters, this creature deals 2 damage to that player.

Brash Taunter

Indestructible
Whenever this creature is dealt damage, it deals that much damage to target opponent.
{2}{R}, {T}: This creature fights another target creature.

Boiling Seas

Oxidda Golem

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

Mogg Maniac

Whenever this creature is dealt damage, it deals that much damage to target opponent or planeswalker.

Arcbond

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

Blazing Sunsteel

Equipped creature gets +1/+0 for each opponent you have.
Whenever equipped creature is dealt damage, it deals that much damage to any target.
Equip {4}

Roiling Vortex

At the beginning of each player's upkeep, this enchantment deals 1 damage to them.
Whenever a player casts a spell, if no mana was spent to cast that spell, this enchantment deals 5 damage to that player.
{R}: Your opponents can't gain life this turn.