Mountain

Geothermal Bog

({T}: Add {B} or {R}.)
Geothermal Bog enters tapped.

Wooded Ridgeline

({T}: Add {R} or {G}.)
Wooded Ridgeline enters tapped.

Eureka Moment

Draw two cards. You may put a land card from your hand onto the battlefield.

Explore

You may play an additional land this turn.
Draw a card.

Canyon Slough

({T}: Add {B} or {R}.)
Canyon Slough enters tapped.
Cycling {2} ({2}, Discard this card: Draw a card.)

Ruin Grinder

Menace
When Ruin Grinder dies, each player may discard their hand and draw seven cards.
Mountaincycling {2} ({2}, Discard this card: Search your library for a Mountain card, reveal it, put it into your hand, then shuffle.)

Volatile Fjord

({T}: Add {U} or {R}.)
Volatile Fjord enters tapped.

Scalding Tarn

{T}, Pay 1 life, Sacrifice Scalding Tarn: Search your library for an Island or Mountain card, put it onto the battlefield, then shuffle.

Granite Grip

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

Smoldering Marsh

({T}: Add {B} or {R}.)
Smoldering Marsh enters tapped unless you control two or more basic lands.

Aesi, Tyrant of Gyre Strait

You may play an additional land on each of your turns.
Landfall — Whenever a land you control enters, you may draw a card.

Valley Rannet

Mountaincycling {2}, forestcycling {2} ({2}, Discard this card: Search your library for a Mountain or Forest card, reveal it, put it into your hand, then shuffle.)

Rockslide Ambush

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

Oracle of Mul Daya

You may play an additional land on each of your turns.
Play with the top card of your library revealed.
You may play lands from the top of your library.

Sakura-Tribe Scout

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

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.

Spoils of Victory

Search your library for a Plains, Island, Swamp, Mountain, or Forest card and put that card onto the battlefield. Then shuffle.

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.

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.

Savai Triome

({T}: Add {R}, {W}, or {B}.)
Savai Triome enters tapped.
Cycling {3} ({3}, Discard this card: Draw a card.)

Tiller Engine

Whenever a land you control enters tapped, choose one —
• Untap that land.
• Tap target nonland permanent an opponent controls.

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.'"

Keeper of Progenitus

Whenever a player taps a Mountain, Forest, or Plains for mana, that player adds one mana of any type that land produced.

Chained to the Rocks

Enchant Mountain you control
When Chained to the Rocks enters, exile target creature an opponent controls until Chained to the Rocks leaves the battlefield. (That creature returns under its owner's control.)

Exploration

You may play an additional land on each of your turns.

Tatyova, Benthic Druid

Landfall — Whenever a land you control enters, you gain 1 life and draw a card.

Escape to the Wilds

Exile the top five cards of your library. You may play cards exiled this way until the end of your next turn.
You may play an additional land this turn.

Bloodstained Mire

{T}, Pay 1 life, Sacrifice Bloodstained Mire: Search your library for a Swamp or Mountain card, put it onto the battlefield, then shuffle.

Kynaios and Tiro of Meletis

At the beginning of your end step, draw a card. Each player may put a land card from their hand onto the battlefield, then each opponent who didn't draws a card.

Abundant Harvest

Choose land or nonland. Reveal cards from the top of your library until you reveal a card of the chosen kind. Put that card into your hand and the rest on the bottom of your library in a random order.

Rampant Growth

Search your library for a basic land card, put that card onto the battlefield tapped, then shuffle.

Lotus Cobra

Landfall — Whenever a land you control enters, add one mana of any color.

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.

Flameshot

You may discard a Mountain card rather than pay this spell's mana cost.
Flameshot deals 3 damage divided as you choose among one, two, or three target creatures.

Alpine Meadow

({T}: Add {R} or {W}.)
Alpine Meadow enters tapped.

Sacred Peaks

({T}: Add {R} or {W}.)
Sacred Peaks enters tapped.

Garth One-Eye

{T}: Choose a card name that hasn't been chosen from among Disenchant, Braingeyser, Terror, Shivan Dragon, Regrowth, and Black Lotus. Create a copy of the card with the chosen name. You may cast the copy. (You still pay its costs.)

Cleansing Wildfire

Destroy target land. Its controller may search their library for a basic land card, put it onto the battlefield tapped, then shuffle.
Draw a card.

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.

Azusa, Lost but Seeking

You may play two additional lands on each of your turns.

Ben-Ben, Akki Hermit

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

Shard Convergence

Search your library for a Plains card, an Island card, a Swamp card, and a Mountain card. Reveal those cards, put them into your hand, then shuffle.

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.

Xander's Lounge

({T}: Add {U}, {B}, or {R}.)
Xander's Lounge enters tapped.
Cycling {3} ({3}, Discard this card: Draw a card.)

Farseek

Search your library for a Plains, Island, Swamp, or Mountain card, put it onto the battlefield tapped, then shuffle.

Ziatora's Proving Ground

({T}: Add {B}, {R}, or {G}.)
Ziatora's Proving Ground enters tapped.
Cycling {3} ({3}, Discard this card: Draw a card.)

Wooded Foothills

{T}, Pay 1 life, Sacrifice Wooded Foothills: Search your library for a Mountain or Forest card, put it onto the battlefield, then shuffle.

Spawn of Thraxes

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

Nahiri's Lithoforming

Sacrifice X lands. For each land sacrificed this way, draw a card. You may play X additional lands this turn. Lands you control enter tapped this turn.

Spitting Earth

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

Song of Creation

You may play an additional land on each of your turns.
Whenever you cast a spell, draw two cards.
At the beginning of your end step, discard your hand.

Elvish Reclaimer

Elvish Reclaimer gets +2/+2 as long as there are three or more land cards in your graveyard.
{2}, {T}, Sacrifice a land: Search your library for a land card, put it onto the battlefield tapped, then shuffle.

Expedition Map

{2}, {T}, Sacrifice this artifact: Search your library for a land card, reveal it, put it into your hand, then shuffle.

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.

Stomping Ground

({T}: Add {R} or {G}.)
As Stomping Ground enters, you may pay 2 life. If you don't, it enters tapped.

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."

Seismic Strike

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

Crop Rotation

As an additional cost to cast this spell, sacrifice a land.
Search your library for a land card, put that card onto the battlefield, then shuffle.

Igneous Pouncer

Haste
Swampcycling {2}, mountaincycling {2} ({2}, Discard this card: Search your library for a Swamp or Mountain card, reveal it, put it into your hand, then shuffle.)

Jetmir's Garden

({T}: Add {R}, {G}, or {W}.)
Jetmir's Garden enters tapped.
Cycling {3} ({3}, Discard this card: Draw a card.)

Sylvan Scrying

Search your library for a land card, reveal it, put it into your hand, then shuffle.

Raugrin Triome

({T}: Add {U}, {R}, or {W}.)
Raugrin Triome enters tapped.
Cycling {3} ({3}, Discard this card: Draw a card.)

Kodama's Reach

Search your library for up to two basic land cards, reveal those cards, put one onto the battlefield tapped and the other into your hand, then shuffle.

Harrow

As an additional cost to cast this spell, sacrifice a land.
Search your library for up to two basic land cards, put them onto the battlefield, then shuffle.

Sulfurous Mire

({T}: Add {B} or {R}.)
Sulfurous Mire enters tapped.

Chartooth Cougar

{R}: Chartooth Cougar gets +1/+0 until end of turn.
Mountaincycling {2} ({2}, Discard this card: Search your library for a Mountain card, reveal it, put it into your hand, then shuffle.)

Claws of Valakut

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

Molten Tributary

({T}: Add {U} or {R}.)
Molten Tributary enters tapped.

Cinder Glade

({T}: Add {R} or {G}.)
Cinder Glade enters tapped unless you control two or more basic lands.

Sheltered Thicket

({T}: Add {R} or {G}.)
Sheltered Thicket enters tapped.
Cycling {2} ({2}, Discard this card: Draw a card.)

Sacred Foundry

({T}: Add {R} or {W}.)
As Sacred Foundry enters, you may pay 2 life. If you don't, it enters tapped.

Eternal Flame

Eternal Flame deals X damage to target opponent or planeswalker and half X damage, rounded up, to you, where X is the number of Mountains you control.

Gem of Becoming

{3}, {T}, Sacrifice Gem of Becoming: Search your library for an Island card, a Swamp card, and a Mountain card. Reveal those cards, put them into your hand, then shuffle.

Arid Mesa

{T}, Pay 1 life, Sacrifice Arid Mesa: Search your library for a Mountain or Plains card, put it onto the battlefield, then shuffle.

Sakura-Tribe Elder

Sacrifice Sakura-Tribe Elder: Search your library for a basic land card, put that card onto the battlefield tapped, then shuffle.

Trade Routes

{1}: Return target land you control to its owner's hand.
{1}, Discard a land card: Draw a card.

Ketria Triome

({T}: Add {G}, {U}, or {R}.)
Ketria Triome enters tapped.
Cycling {3} ({3}, Discard this card: Draw a card.)

Tireless Provisioner

Landfall — Whenever a land you control enters, create a Food token or a Treasure token. (Food is an artifact with "{2}, {T}, Sacrifice this artifact: You gain 3 life." Treasure is an artifact with "{T}, Sacrifice this artifact: Add one mana of any color.")

Mina and Denn, Wildborn

You may play an additional land on each of your turns.
{R}{G}, Return a land you control to its owner's hand: Target creature gains trample until end of turn.

Spire Barrage

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

Blood Crypt

({T}: Add {B} or {R}.)
As Blood Crypt enters, you may pay 2 life. If you don't, it enters tapped.

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}.

Ancient Greenwarden

Reach (This creature can block creatures with flying.)
You may play lands from your graveyard.
If a land entering the battlefield causes a triggered ability of a permanent you control to trigger, that ability triggers an additional time.

Highland Forest

({T}: Add {R} or {G}.)
Highland Forest enters tapped.

Burgeoning

Whenever an opponent plays a land, you may put a land card from your hand onto the battlefield.

Cultivate

Goblin Charbelcher

{3}, {T}: Reveal cards from the top of your library until you reveal a land card. Goblin Charbelcher deals damage equal to the number of nonland cards revealed this way to any target. If the revealed land card was a Mountain, Goblin Charbelcher deals double that damage instead. Put the revealed cards on the bottom of your library in any order.

Steam Vents

({T}: Add {U} or {R}.)
As Steam Vents enters, you may pay 2 life. If you don't, it enters tapped.