Embodiment of Fury

Trample
Land creatures you control have trample.
Landfall — Whenever a land you control enters, you may have target land you control become a 3/3 Elemental creature with haste until end of turn. It's still a land.

Fires of Mount Doom

When Fires of Mount Doom enters, it deals 2 damage to target creature an opponent controls. Destroy all Equipment attached to that creature.
{2}{R}: Exile the top card of your library. You may play that card this turn. When you play a card this way, Fires of Mount Doom deals 2 damage to each player.

Tunnel Ignus

Whenever a land enters under an opponent's control, if that player had another land enter the battlefield under their control this turn, Tunnel Ignus deals 3 damage to that player.

Castle Embereth

Castle Embereth enters tapped unless you control a Mountain.
{T}: Add {R}.
{1}{R}{R}, {T}: Creatures you control get +1/+0 until end of turn.

Searing Blaze

Searing Blaze deals 1 damage to target player or planeswalker and 1 damage to target creature that player or that planeswalker's controller controls.
Landfall — If you had a land enter the battlefield under your control this turn, Searing Blaze deals 3 damage to that player or planeswalker and 3 damage to that creature instead.

Seismic Strike

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

Skoa, Embermage

When Skoa, Embermage enters, it deals 4 damage to any target.
Grandeur — Discard another card named Skoa, Embermage, Sacrifice two Mountains: Skoa deals 4 damage to any target.

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.

Volcanic Geyser

Volcanic Geyser deals X damage to any target.

Granite Grip

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

Spitfire Bastion

(Transforms from Vance's Blasting Cannons.)
{T}: Add {R}.
{2}{R}, {T}: Spitfire Bastion deals 3 damage to any target.

Vance's Blasting Cannons

At the beginning of your upkeep, exile the top card of your library. If it's a nonland card, you may cast that card this turn.
Whenever you cast your third spell in a turn, you may transform Vance's Blasting Cannons.

Vance's Blasting Cannons // Spitfire Bastion

Zo-Zu the Punisher

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

Lava Burst

Lava Burst deals X damage to any target. If Lava Burst would deal damage to a creature, that damage can't be prevented or dealt instead to another permanent or player.

Spitfire Lagac

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

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.'"

Mountain

Belligerent Whiptail

Landfall — Whenever a land you control enters, Belligerent Whiptail gains first strike until end of turn.

Blood Moon

Genju of the Spires

Enchant Mountain
{2}: Enchanted Mountain becomes a 6/1 red Spirit creature until end of turn. It's still a land.
When enchanted Mountain is put into a graveyard, you may return Genju of the Spires from your graveyard to your hand.

Terramorphic Expanse

{T}, Sacrifice Terramorphic Expanse: Search your library for a basic land card, put it onto the battlefield tapped, then shuffle.

Ruby Medallion

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

Rockslide Ambush

Rockslide Ambush deals damage to target creature equal to the number of Mountains you control.

Sardian Cliffstomper

As long as it's your turn and you control four or more Mountains, Sardian Cliffstomper gets +X/+0, where X is the number of Mountains you control.

Zektar Shrine Expedition

Landfall — Whenever a land you control enters, you may put a quest counter on Zektar Shrine Expedition.
Remove three quest counters from Zektar Shrine Expedition and sacrifice it: Create a 7/1 red Elemental creature token with trample and haste. Exile it at the beginning of the next end step.

Anger

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

Lavabrink Floodgates

{T}: Add {R}{R}.
At the beginning of each player's upkeep, that player may put a doom counter on Lavabrink Floodgates or remove a doom counter from it. Then if it has three or more doom counters on it, sacrifice Lavabrink Floodgates. When you do, it deals 6 damage to each creature.

Hidden Volcano

Hidden Volcano enters tapped.
{T}: Add {R}.
{4}{R}, {T}, Sacrifice Hidden Volcano: Discover 4. Activate only as a sorcery. (Exile cards from the top of your library until you exile a nonland card with mana value 4 or less. Cast it without paying its mana cost or put it into your hand. Put the rest on the bottom in a random order.)

Volcanic Hammer

Volcanic Hammer deals 3 damage to any target.

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}.

Annihilating Fire

Annihilating Fire deals 3 damage to any target. If a creature dealt damage this way would die this turn, exile it instead.

Diamond Knight

Vigilance (Attacking doesn't cause this creature to tap.)
As Diamond Knight enters, choose a color.
Whenever you cast a spell of the chosen color, put a +1/+1 counter on Diamond Knight.

Awaken the Ancient

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

Mine Collapse

If it's your turn, you may sacrifice a Mountain rather than pay this spell's mana cost.
Mine Collapse deals 5 damage to target creature or planeswalker.

Magus of the Moon

Oxidda Golem

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

Circle of Flame

Whenever a creature without flying attacks you or a planeswalker you control, Circle of Flame deals 1 damage to that creature.

Madblind Mountain

({T}: Add {R}.)
Madblind Mountain enters tapped.
{R}, {T}: Shuffle your library. Activate only if you control two or more red permanents.

Fire Diamond

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

Exuberant Firestoker

At the beginning of your end step, if you control a creature with power 5 or greater, you may have Exuberant Firestoker deal 2 damage to target player or planeswalker.
{T}: Add {C}.

Lavaspur Boots

Equipped creature gets +1/+0 and has haste and ward {1}. (Whenever it becomes the target of a spell or ability an opponent controls, counter it unless that player pays {1}.)
Equip {1}

Evolving Wilds

{T}, Sacrifice this land: Search your library for a basic land card, put it onto the battlefield tapped, then shuffle.

Balefire Dragon

Flying
Whenever Balefire Dragon deals combat damage to a player, it deals that much damage to each creature that player controls.

Sword of Fire and Ice

Equipped creature gets +2/+2 and has protection from red and from blue.
Whenever equipped creature deals combat damage to a player, Sword of Fire and Ice deals 2 damage to any target and you draw a card.
Equip {2}

Spawn of Thraxes

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

Scorching Lava

Kicker {R} (You may pay an additional {R} as you cast this spell.)
Scorching Lava deals 2 damage to any target. If this spell was kicked, that creature can't be regenerated this turn and if it would die this turn, exile it instead.

Satyr Firedancer

Whenever an instant or sorcery spell you control deals damage to an opponent, Satyr Firedancer deals that much damage to target creature that player controls.

Sol Ring

Koth, Fire of Resistance

+2: Search your library for a basic Mountain card, reveal it, put it into your hand, then shuffle.
−3: Koth, Fire of Resistance deals damage to target creature equal to the number of Mountains you control.
−7: You get an emblem with "Whenever a Mountain you control enters, this emblem deals 4 damage to any target."

Pulverize

You may sacrifice two Mountains rather than pay this spell's mana cost.
Destroy all artifacts.

Volcanic Wind

Volcanic Wind deals X damage divided as you choose among any number of target creatures, where X is the number of creatures on the battlefield as you cast this spell.

Lava Axe

Lava Axe deals 5 damage to target player or planeswalker.

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.

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}.

Crash

You may sacrifice a Mountain rather than pay this spell's mana cost.
Destroy target artifact.

Spire Barrage

Spire Barrage 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.

Wildfire Eternal

Afflict 4 (Whenever this creature becomes blocked, defending player loses 4 life.)
Whenever Wildfire Eternal attacks and isn't blocked, you may cast an instant or sorcery spell from your hand without paying its mana cost.

Lavaball Trap

If an opponent had two or more lands enter the battlefield under their control this turn, you may pay {3}{R}{R} rather than pay this spell's mana cost.
Destroy two target lands. Lavaball Trap deals 4 damage to each creature.

Valakut Exploration

Landfall — Whenever a land you control enters, exile the top card of your library. You may play that card for as long as it remains exiled.
At the beginning of your end step, if there are cards exiled with Valakut Exploration, put them into their owner's graveyard, then Valakut Exploration deals that much damage to each opponent.

Alpine Guide

When Alpine Guide enters, you may search your library for a Mountain card, put that card onto the battlefield tapped, then shuffle.
Alpine Guide attacks each combat if able.
When Alpine Guide leaves the battlefield, sacrifice a Mountain.

Geode Rager

First strike
Landfall — Whenever a land you control enters, goad each creature target player controls. (Until your next turn, those creatures attack each combat if able and attack a player other than you if able.)

The First Eruption

(As this Saga enters and after your draw step, add a lore counter. Sacrifice after III.)
I — The First Eruption deals 1 damage to each creature without flying.
II — Add {R}{R}.
III — Sacrifice a Mountain. If you do, The First Eruption deals 3 damage to each creature.

Spitting Earth

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

Staff of the Flame Magus

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

Cosi's Ravager

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

Arcane Signet

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

Diamond Mare

As Diamond Mare enters, choose a color.
Whenever you cast a spell of the chosen color, you gain 1 life.

Fire Dragon

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

Themberchaud

Trample
When Themberchaud enters, he deals X damage to each other creature without flying and each player, where X is the number of Mountains you control.
You may exert Themberchaud as he attacks. When you do, he gains flying until end of turn. (An exerted creature won't untap during your next untap step.)

Nesting Dragon

Flying
Landfall — Whenever a land you control enters, create a 0/2 red Dragon Egg creature token with defender and "When this creature dies, create a 2/2 red Dragon creature token with flying and '{R}: This creature gets +1/+0 until end of turn.'"

Tunneling Geopede

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

Earth Servant

Earth Servant gets +0/+1 for each Mountain you control.

Ben-Ben, Akki Hermit

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

Dwarven Mine

({T}: Add {R}.)
Dwarven Mine enters tapped unless you control three or more other Mountains.
When Dwarven Mine enters untapped, create a 1/1 red Dwarf creature token.

Arena of Glory

Arena of Glory enters tapped unless you control a Mountain.
{T}: Add {R}.
{R}, {T}, Exert Arena of Glory: Add {R}{R}. If that mana is spent on a creature spell, it gains haste until end of turn. (An exerted permanent won't untap during your next untap step.)

Lava Coil

Lava Coil deals 4 damage to target creature. If that creature would die this turn, exile it instead.