Mountain

Simian Spirit Guide

Exile Simian Spirit Guide from your hand: Add {R}.

Mana Geyser

Add {R} for each tapped land your opponents control.

Honor-Worn Shaku

{T}: Add {C}.
Tap an untapped legendary permanent you control: Untap Honor-Worn Shaku.

Goblin Welder

{T}: Choose target artifact a player controls and target artifact card in that player's graveyard. If both targets are still legal as this ability resolves, that player simultaneously sacrifices the artifact and returns the artifact card to the battlefield.

Heart of Ramos

{T}: Add {R}.
Sacrifice Heart of Ramos: Add {R}.

Rite of Flame

Add {R}{R}, then add {R} for each card named Rite of Flame in each graveyard.

Arcane Signet

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

Iron Myr

Deflecting Swat

If you control a commander, you may cast this spell without paying its mana cost.
You may choose new targets for target spell or ability.

Ruby Medallion

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

Gamble

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

Pyroblast

Choose one —
• Counter target spell if it's blue.
• Destroy target permanent if it's blue.

Seething Song

Command Beacon

{T}: Add {C}.
{T}, Sacrifice Command Beacon: Put your commander into your hand from the command zone.

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.

Geosurge

Add {R}{R}{R}{R}{R}{R}{R}. Spend this mana only to cast artifact or creature spells.

Manifold Key

{1}, {T}: Untap another target artifact.
{3}, {T}: Target creature can't be blocked this turn.

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.

Thran Dynamo

Prismatic Lens

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

Fork

Copy target instant or sorcery spell, except that the copy is red. You may choose new targets for the copy.

Mind Stone

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

Basalt Monolith

Basalt Monolith doesn't untap during your untap step.
{T}: Add {C}{C}{C}.
{3}: Untap Basalt Monolith.

Sol Ring

Defense Grid

Each spell costs {3} more to cast except during its controller's turn.

Thought Vessel

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

Cryptic Trilobite

Cryptic Trilobite enters with X +1/+1 counters on it.
Remove a +1/+1 counter from Cryptic Trilobite: Add {C}{C}. Spend this mana only to activate abilities.
{1}, {T}: Put a +1/+1 counter on Cryptic Trilobite.

Pyretic Ritual

Godo, Bandit Warlord

When Godo, Bandit Warlord enters, you may search your library for an Equipment card, put it onto the battlefield, then shuffle.
Whenever Godo attacks for the first time each turn, untap it and all Samurai you control. After this phase, there is an additional combat phase.

Dwarven Ruins

Dwarven Ruins enters tapped.
{T}: Add {R}.
{T}, Sacrifice Dwarven Ruins: Add {R}{R}.

Worn Powerstone

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

Irencrag Feat

Add seven {R}. You can cast only one more spell this turn.

Ricochet Trap

If an opponent cast a blue spell this turn, you may pay {R} rather than pay this spell's mana cost.
Change the target of target spell with a single target.

Vessel of Volatility

{1}{R}, Sacrifice Vessel of Volatility: Add {R}{R}{R}{R}.

Warrior's Oath

Take an extra turn after this one. At the beginning of that turn's end step, you lose the game.

Hammer of Nazahn

Whenever Hammer of Nazahn or another Equipment you control enters, you may attach that Equipment to target creature you control.
Equipped creature gets +2/+0 and has indestructible.
Equip {4}

Final Fortune

Reckless Barbarian

Sacrifice Reckless Barbarian: Add {R}{R}.

Palladium Myr

Desperate Ritual

Add {R}{R}{R}.
Splice onto Arcane {1}{R} (As you cast an Arcane spell, you may reveal this card from your hand and pay its splice cost. If you do, add this card's effects to that spell.)

Magus of the Moon

Conqueror's Flail

Equipped creature gets +1/+1 for each color among permanents you control.
As long as Conqueror's Flail is attached to a creature, your opponents can't cast spells during your turn.
Equip {2}

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}

Buried Ruin

{T}: Add {C}.
{2}, {T}, Sacrifice Buried Ruin: Return target artifact card from your graveyard to your hand.

Jeska's Will

Choose one. If you control a commander as you cast this spell, you may choose both instead.
• Add {R} for each card in target opponent's hand.
• Exile the top three cards of your library. You may play them this turn.

Brass Squire

{T}: Attach target Equipment you control to target creature you control.

Fellwar Stone

{T}: Add one mana of any color that a land an opponent controls could produce.

Crystal Vein

{T}: Add {C}.
{T}, Sacrifice Crystal Vein: Add {C}{C}.

Mana Web

Whenever a land an opponent controls is tapped for mana, tap all lands that player controls that could produce any type of mana that land could produce.

Fire Diamond

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

Abrade

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

Red Elemental Blast

Choose one —
• Counter target blue spell.
• Destroy target blue permanent.

Mox Amber

{T}: Add one mana of any color among legendary creatures and planeswalkers you control.

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}.

Glittering Stockpile

{T}: Add {R}. Put a stash counter on Glittering Stockpile.
{T}, Sacrifice Glittering Stockpile: Add X mana of any one color, where X is the number of stash counters on Glittering Stockpile.

Lotus Petal

{T}, Sacrifice Lotus Petal: Add one mana of any color.

Last Chance

Magnetic Theft

Attach target Equipment to target creature. (Control of the Equipment doesn't change.)

Sandstone Needle

Sandstone Needle enters tapped with two depletion counters on it.
{T}, Remove a depletion counter from Sandstone Needle: Add {R}{R}. If there are no depletion counters on Sandstone Needle, sacrifice it.

Hedron Archive

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

Generator Servant

{T}, Sacrifice Generator Servant: Add {C}{C}. If that mana is spent on a creature spell, it gains haste until end of turn. (That creature can attack and {T} as soon as it comes under your control.)

Emergence Zone

{T}: Add {C}.
{1}, {T}, Sacrifice Emergence Zone: You may cast spells this turn as though they had flash.

Blood Moon

Voltaic Key

Cursed Mirror

{T}: Add {R}.
As Cursed Mirror enters, you may have it become a copy of any creature on the battlefield until end of turn, except it has haste.

Return the Favor

Spree (Choose one or more additional costs.)
+ {1} — Copy target instant spell, sorcery spell, activated ability, or triggered ability. You may choose new targets for the copy.
+ {1} — Change the target of target spell or ability with a single target.