Spark of Creativity

Choose target creature. Exile the top card of your library. You may have Spark of Creativity deal damage to that creature equal to the exiled card's mana value. If you don't, you may play that card until end of turn.

Forgotten Cave

Forgotten Cave enters tapped.
{T}: Add {R}.
Cycling {R} ({R}, Discard this card: Draw a card.)

Ancient Stone Idol

Flash
This spell costs {1} less to cast for each attacking creature.
Trample
When Ancient Stone Idol dies, create a 6/12 colorless Construct artifact creature token with trample.

War Room

{T}: Add {C}.
{3}, {T}, Pay life equal to the number of colors in your commanders' color identity: Draw a card.

Hazoret's Monument

Red creature spells you cast cost {1} less to cast.
Whenever you cast a creature spell, you may discard a card. If you do, draw a card.

Priest of Urabrask

When Priest of Urabrask enters, add {R}{R}{R}.

Seething Song

The Autonomous Furnace

The Autonomous Furnace enters tapped.
{T}: Add {R}.
{1}{R}, {T}, Sacrifice The Autonomous Furnace: Draw a card.

Evolving Wilds

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

Magmatic Insight

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

Mana Geyser

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

Rogue's Passage

{T}: Add {C}.
{4}, {T}: Target creature can't be blocked this turn.

Irencrag Feat

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

Bloodsworn Steward

Flying
Commander creatures you control get +2/+2 and have haste.

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}

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.)

Sandstone Oracle

Flying
When Sandstone Oracle enters, choose an opponent. If that player has more cards in hand than you, draw cards equal to the difference.

Unexpected Windfall

As an additional cost to cast this spell, discard a card.
Draw two cards and create two Treasure tokens. (They're artifacts with "{T}, Sacrifice this artifact: Add one mana of any color.")

Expedite

Target creature gains haste until end of turn.
Draw a card.

Swiftfoot Boots

Equipped creature has hexproof and haste. (It can't be the target of spells or abilities your opponents control.)
Equip {1}

Spawn of Thraxes

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

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.

Tyrite Sanctum

{T}: Add {C}.
{2}, {T}: Target legendary creature becomes a God in addition to its other types. Put a +1/+1 counter on it.
{4}, {T}, Sacrifice Tyrite Sanctum: Put an indestructible counter on target God.

Terror of Mount Velus

Flying, double strike
When Terror of Mount Velus enters, creatures you control gain double strike until end of turn.

Blast-Furnace Hellkite

Artifact offering (You may cast this spell as thought it had flash by sacrificing an artifact and paying the difference in mana costs between this and the sacrificed artifact. Mana cost includes color.)
Flying, double strike
Creatures attacking your opponents have double strike.

Cathartic Reunion

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

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.

Neheb, the Eternal

Afflict 3 (Whenever this creature becomes blocked, defending player loses 3 life.)
At the beginning of each of your postcombat main phases, add {R} for each 1 life your opponents have lost this turn.

Combustible Gearhulk

First strike
When Combustible Gearhulk enters, target opponent may have you draw three cards. If the player doesn't, you mill three cards, then Combustible Gearhulk deals damage to that player equal to the total mana value of those cards.

Fire Diamond

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

Flameshadow Conjuring

Whenever a nontoken creature you control enters, you may pay {R}. If you do, create a token that's a copy of that creature. That token gains haste. Exile it at the beginning of the next end step.

Anzrag's Rampage

Destroy all artifacts you don't control, then exile the top X cards of your library, where X is the number of artifacts that were put into graveyards from the battlefield this turn. You may put a creature card exiled this way onto the battlefield. It gains haste. Return it to your hand at the beginning of the next end step.

Mountain

Commander's Sphere

{T}: Add one mana of any color in your commander's color identity.
Sacrifice Commander's Sphere: Draw a card.

Dragon Tyrant

Flying, trample
Double strike (This creature deals both first-strike and regular combat damage.)
At the beginning of your upkeep, sacrifice Dragon Tyrant unless you pay {R}{R}{R}{R}.
{R}: Dragon Tyrant gets +1/+0 until end of turn.

Fellwar Stone

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

Palladium Myr

Whispersilk Cloak

Equipped creature can't be blocked and has shroud. (It can't be the target of spells or abilities.)
Equip {2}

Breaker of Armies

All creatures able to block Breaker of Armies do so.

Thrill of Possibility

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

Where Ancients Tread

Whenever a creature you control with power 5 or greater enters, you may have Where Ancients Tread deal 5 damage to any target.

Mind Stone

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

Urabrask the Hidden

Creatures you control have haste.
Creatures your opponents control enter tapped.

Iron Myr

Arcane Signet

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

Bolt Bend

This spell costs {3} less to cast if you control a creature with power 4 or greater.
Change the target of target spell or ability with a single target.

Sol Ring

Bogardan Hellkite

Flash
Flying
When Bogardan Hellkite enters, it deals 5 damage divided as you choose among any number of targets.

Hour of Devastation

All creatures lose indestructible until end of turn. Hour of Devastation deals 5 damage to each creature and each non-Bolas planeswalker.

Spinerock Knoll

Hideaway 4 (When this land enters, look at the top four cards of your library, exile one face down, then put the rest on the bottom in a random order.)
Spinerock Knoll enters tapped.
{T}: Add {R}.
{R}, {T}: You may play the exiled card without paying its mana cost if an opponent was dealt 7 or more damage this turn.

Avatar of Slaughter

All creatures have double strike and attack each combat if able.

Lightning Greaves

Equipped creature has haste and shroud. (It can't be the target of spells or abilities.)
Equip {0}

Endless Atlas

{2}, {T}: Draw a card. Activate only if you control three or more lands with the same name.

Anger

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

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.

Ox of Agonas

When Ox of Agonas enters, discard your hand, then draw three cards.
Escape—{R}{R}, Exile eight other cards from your graveyard. (You may cast this card from your graveyard for its escape cost.)
Ox of Agonas escapes with a +1/+1 counter on it.

Warstorm Surge

Whenever a creature you control enters, it deals damage equal to its power to any target.

Etali, Primal Storm

Whenever Etali, Primal Storm attacks, exile the top card of each player's library, then you may cast any number of spells from among those cards without paying their mana costs.

Tyrant of Discord

When Tyrant of Discord enters, target opponent chooses a permanent they control at random and sacrifices it. If a nonland permanent is sacrificed this way, repeat this process.

Arni Metalbrow

Whenever a creature you control attacks or a creature you control enters attacking, you may pay {1}{R}. If you do, you may put a creature card with mana value less than that creature's mana value from your hand onto the battlefield tapped and attacking.

Burnished Hart

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

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.

Terramorphic Expanse

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

Solemn Simulacrum

When Solemn Simulacrum enters, you may search your library for a basic land card, put that card onto the battlefield tapped, then shuffle.
When Solemn Simulacrum dies, you may 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.

Sunbird's Invocation

Whenever you cast a spell from your hand, reveal the top X cards of your library, where X is that spell's mana value. You may cast a spell with mana value X or less from among cards revealed this way without paying its mana cost. Put the rest on the bottom of your library in a random order.

Bonders' Enclave

{T}: Add {C}.
{3}, {T}: Draw a card. Activate only if you control a creature with power 4 or greater.

Goldhound

First strike
Menace (This creature can't be blocked except by two or more creatures.)
{T}, Sacrifice Goldhound: Add one mana of any color.

Hedron Archive

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

Thundermare

Haste (This creature can attack and {T} as soon as it comes under your control.)
When Thundermare enters, tap all other creatures.

Dragon Mage

Flying
Whenever Dragon Mage deals combat damage to a player, each player discards their hand, then draws seven cards.

Ilharg, the Raze-Boar

Trample
Whenever Ilharg, the Raze-Boar attacks, you may put a creature card from your hand onto the battlefield tapped and attacking. Return that creature to your hand at the beginning of the next end step.
When Ilharg, the Raze-Boar dies or is put into exile from the battlefield, you may put it into its owner's library third from the top.

Big Score

Meteor Golem

When Meteor Golem enters, destroy target nonland permanent an opponent controls.