Fellwar Stone

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

Prismatic Lens

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

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}.

Rolling Earthquake

Rolling Earthquake deals X damage to each creature without horsemanship and each player.

Boros Signet

Sacred Foundry

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

Chandra, Torch of Defiance

+1: Exile the top card of your library. You may cast that card. If you don't, Chandra, Torch of Defiance deals 2 damage to each opponent.
+1: Add {R}{R}.
−3: Chandra, Torch of Defiance deals 4 damage to target creature.
−7: You get an emblem with "Whenever you cast a spell, this emblem deals 5 damage to any target."

Rip Apart

Choose one —
• Rip Apart deals 3 damage to target creature or planeswalker.
• Destroy target artifact or enchantment.

Mind's Eye

Whenever an opponent draws a card, you may pay {1}. If you do, draw a card.

Reckless Endeavor

Roll two d12 and choose one result. Reckless Endeavor deals damage equal to that result to each creature. Then create a number of Treasure tokens equal to the other result.

Sol Ring

Darksteel Plate

Indestructible
Equipped creature has indestructible.
Equip {2}

Brightflame

Radiance — Brightflame deals X damage to target creature and each other creature that shares a color with it. You gain life equal to the damage dealt this way.

Repercussion

Whenever a creature is dealt damage, Repercussion deals that much damage to that creature's controller.

Deflecting Palm

The next time a source of your choice would deal damage to you this turn, prevent that damage. If damage is prevented this way, Deflecting Palm deals that much damage to that source's controller.

Spectator Seating

Spectator Seating enters tapped unless you have two or more opponents.
{T}: Add {R} or {W}.

Marble Diamond

Marble Diamond enters tapped.
{T}: Add {W}.

Torrent of Lava

Torrent of Lava deals X damage to each creature without flying.
As long as Torrent of Lava is on the stack, each creature has "{T}: Prevent the next 1 damage that would be dealt to this creature by Torrent of Lava this turn."

Mana Geyser

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

Lightning Helix

Lightning Helix deals 3 damage to any target and you gain 3 life.

Aetherflux Reservoir

Whenever you cast a spell, you gain 1 life for each spell you've cast this turn.
Pay 50 life: Aetherflux Reservoir deals 50 damage to any target.

Gilded Lotus

Unbreakable Formation

Creatures you control gain indestructible until end of turn.
Addendum — If you cast this spell during your main phase, put a +1/+1 counter on each of those creatures and they gain vigilance until end of turn.

Alpine Meadow

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

Earthquake

Earthquake deals X damage to each creature without flying and each player.

Gift of Immortality

Enchant creature
When enchanted creature dies, return that card to the battlefield under its owner's control. Return Gift of Immortality to the battlefield attached to that creature at the beginning of the next end step.

Truefire Captain

Mentor (Whenever this creature attacks, put a +1/+1 counter on target attacking creature with lesser power.)
Whenever Truefire Captain is dealt damage, it deals that much damage to target player.

Timely Ward

You may cast Timely Ward as though it had flash if it targets a commander.
Enchant creature
Enchanted creature has indestructible.

Indestructibility

Enchant permanent
Enchanted permanent has indestructible. (Effects that say "destroy" don't destroy that permanent. A creature with indestructible can't be destroyed by damage.)

Worn Powerstone

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

Mizzium Mortars

Mizzium Mortars deals 4 damage to target creature you don't control.
Overload {3}{R}{R}{R} (You may cast this spell for its overload cost. If you do, change "target" in its text to "each.")

Mind Stone

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

Sudden Demise

Choose a color. Sudden Demise deals X damage to each creature of the chosen color.

Pyrohemia

At the beginning of the end step, if no creatures are on the battlefield, sacrifice Pyrohemia.
{R}: Pyrohemia deals 1 damage to each creature and each player.

Thran Dynamo

Alhammarret's Archive

If you would gain life, you gain twice that much life instead.
If you would draw a card except the first one you draw in each of your draw steps, draw two cards instead.

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.

Furycalm Snarl

As Furycalm Snarl enters, you may reveal a Mountain or Plains card from your hand. If you don't, Furycalm Snarl enters tapped.
{T}: Add {R} or {W}.

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}

Pariah

Enchant creature
All damage that would be dealt to you is dealt to enchanted creature instead.

Flawless Maneuver

If you control a commander, you may cast this spell without paying its mana cost.
Creatures you control gain indestructible until end of turn.

Rolling Thunder

Rolling Thunder deals X damage divided as you choose among any number of targets.

Firesong and Sunspeaker

Red instant and sorcery spells you control have lifelink.
Whenever a white instant or sorcery spell causes you to gain life, Firesong and Sunspeaker deals 3 damage to target creature or player.

Fire Diamond

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

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}

Star of Extinction

Destroy target land. Star of Extinction deals 20 damage to each creature and each planeswalker.

Molten Disaster

Kicker {R} (You may pay an additional {R} as you cast this spell.)
If this spell was kicked, it has split second. (As long as this spell is on the stack, players can't cast spells or activate abilities that aren't mana abilities.)
Molten Disaster deals X damage to each creature without flying and each player.

Valakut Stoneforge

Valakut Stoneforge enters tapped.
{T}: Add {R}.

Valakut Awakening

Put any number of cards from your hand on the bottom of your library, then draw that many cards plus one.

Valakut Awakening // Valakut Stoneforge

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

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.

Selfless Spirit

Flying
Sacrifice Selfless Spirit: Creatures you control gain indestructible until end of turn.

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.

Spitemare

Whenever Spitemare is dealt damage, it deals that much damage to any target.

The Celestus

If it's neither day nor night, it becomes day as The Celestus enters.
{T}: Add one mana of any color.
{3}, {T}: If it's night, it becomes day. Otherwise, it becomes night. Activate only as a sorcery.
Whenever day becomes night or night becomes day, you gain 1 life. You may draw a card. If you do, discard a card.

Pariah's Shield

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

Solar Blaze

Each creature deals damage to itself equal to its power.

Well of Lost Dreams

Whenever you gain life, you may pay {X}, where X is less than or equal to the amount of life you gained. If you do, draw X cards.

Arcane Signet

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

Boros Reckoner

Whenever Boros Reckoner is dealt damage, it deals that much damage to any target.
{R/W}: Boros Reckoner gains first strike until end of turn.

Mogg Maniac

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

Vandalblast

Destroy target artifact you don't control.
Overload {4}{R} (You may cast this spell for its overload cost. If you do, change "target" in its text to "each.")

Spiteful Sliver

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

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.

Magmaquake

Magmaquake deals X damage to each creature without flying and each planeswalker.

Temple of Triumph

This land enters tapped.
When this land enters, scry 1. (Look at the top card of your library. You may put that card on the bottom.)
{T}: Add {R} or {W}.

Plateau

Blasphemous Act

This spell costs {1} less to cast for each creature on the battlefield.
Blasphemous Act deals 13 damage to each creature.

Starstorm

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

Fault Line

Fault Line deals X damage to each creature without flying and each player.

Skyclave Relic

Kicker {3}
Indestructible
When Skyclave Relic enters, if it was kicked, create two tapped tokens that are copies of Skyclave Relic.
{T}: Add one mana of any color.

Wheel of Misfortune

Each player secretly chooses a number 0 or greater, then all players reveal those numbers simultaneously and determine the highest and lowest numbers revealed this way. Wheel of Misfortune deals damage equal to the highest number to each player who chose that number. Each player who didn't choose the lowest number discards their hand, then draws seven cards.

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.

Chain Reaction

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

Slagstorm

Choose one —
• Slagstorm deals 3 damage to each creature.
• Slagstorm deals 3 damage to each player.

Brash Taunter

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

Boros Charm

Choose one —
• Boros Charm deals 4 damage to target player or planeswalker.
• Permanents you control gain indestructible until end of turn.
• Target creature gains double strike until end of turn.

Sundown Pass

Sundown Pass enters tapped unless you control two or more other lands.
{T}: Add {R} or {W}.

Howlpack Avenger

Whenever a permanent you control is dealt damage, Howlpack Avenger deals that much damage to any target.
{1}{R}: Howlpack Avenger 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 Ill-Tempered Loner is dealt damage, it deals that much damage to any target.
{1}{R}: Ill-Tempered Loner 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

Mountain

Star Compass

Star Compass enters tapped.
{T}: Add one mana of any color that a basic land you control could produce.

Clifftop Retreat

Clifftop Retreat enters tapped unless you control a Mountain or a Plains.
{T}: Add {R} or {W}.

Magebane Armor

Equipped creature gets +2/+4 and loses flying.
Prevent all noncombat damage that would be dealt to equipped creature.
Equip {2} ({2}: Attach to target creature you control. Equip only as a sorcery.)