Big Score

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.")

Mountain

Electric Revelation

As an additional cost to cast this spell, discard a card.
Draw two cards.
Flashback {3}{R} (You may cast this card from your graveyard for its flashback cost and any additional costs. Then exile it.)

Fire Prophecy

Fire Prophecy deals 3 damage to target creature. You may put a card from your hand on the bottom of your library. If you do, draw a card.

Battle Hymn

Mind Stone

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

Destructive Tampering

Choose one —
• Destroy target artifact.
• Creatures without flying can't block this turn.

Tormenting Voice

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

Guardian Idol

Guardian Idol enters tapped.
{T}: Add {C}.
{2}: Guardian Idol becomes a 2/2 Golem artifact creature until end of turn.

Whispersilk Cloak

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

Mana Geyser

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

Burn Bright

Creatures you control get +2/+0 until end of turn.

Cathartic Reunion

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

Collateral Damage

As an additional cost to cast this spell, sacrifice a creature.
Collateral Damage deals 3 damage to any target.

Burning-Tree Vandal

Riot (This creature enters with your choice of a +1/+1 counter or haste.)
Whenever Burning-Tree Vandal attacks, you may discard a card. If you do, draw a card.

Arcane Signet

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

Plundering Barbarian

When Plundering Barbarian enters, choose one —
• Smash the Chest — Destroy target artifact.
• Pry It Open — Create a Treasure token. (It's an artifact with "{T}, Sacrifice this artifact: Add one mana of any color.")

Ornithopter of Paradise

Volatile Claws

Until end of turn, creatures you control get +2/+0 and gain all creature types.

Star Compass

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

Slight Malfunction

Choose one —
• Destroy target artifact.
• Roll a six-sided die. When you do, Slight Malfunction deals 1 damage to each of up to X target creatures, where X is the result.

Faithless Looting

Draw two cards, then discard two cards.
Flashback {2}{R} (You may cast this card from your graveyard for its flashback cost. Then exile it.)

Fire Diamond

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

Smoldering Crater

Smoldering Crater enters tapped.
{T}: Add {R}.
Cycling {2} ({2}, Discard this card: Draw a card.)

Howling Golem

Whenever Howling Golem attacks or blocks, each player draws a card.

Desert of the Fervent

Desert of the Fervent enters tapped.
{T}: Add {R}.
Cycling {1}{R} ({1}{R}, Discard this card: Draw a card.)

Forgotten Cave

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

Clockwork Fox

When Clockwork Fox leaves the battlefield, you draw two cards and each opponent draws a card.

Smash

Impact Tremors

Whenever a creature you control enters, this enchantment deals 1 damage to each opponent.

Manakin

Iron Myr

Ambitious Assault

Creatures you control get +2/+0 until end of turn. If you control a modified creature, draw a card. (Equipment, Auras you control, and counters are modifications.)

Unexpected Windfall

Thrill of Possibility

Thought Vessel

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

Smash to Dust

Choose one —
• Destroy target artifact.
• Destroy target creature with defender.
• Smash to Dust deals 1 damage to each creature your opponents control.

Prismatic Lens

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

Reckless Abandon

As an additional cost to cast this spell, sacrifice a creature.
Reckless Abandon deals 4 damage to any target.

Mad Ratter

Whenever you draw your second card each turn, create two 1/1 black Rat creature tokens.

Lightning Bolt

Lightning Bolt deals 3 damage to any target.

Abrade

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

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.

Dangerous Wager

Witty Roastmaster

Alliance — Whenever another creature you control enters, Witty Roastmaster deals 1 damage to each opponent.

Jalum Tome

{2}, {T}: Draw a card, then discard a card.

Hedron Crawler

{T}: Add {C}. ({C} represents colorless mana.)

Seize the Spoils

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