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.)

Threaten

Untap target creature and gain control of it until end of turn. That creature gains haste until end of turn. (It can attack and {T} this turn.)

Forest

Explosive Vegetation

Search your library for up to two basic land cards, put them onto the battlefield tapped, then shuffle.

Goblin Anarchomancer

Each spell you cast that's red or green costs {1} less to cast.

Dualcaster Mage

Flash
When Dualcaster Mage enters, copy target instant or sorcery spell. You may choose new targets for the copy.

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.")

Command Tower

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

Goblin Gathering

Create a number of 1/1 red Goblin creature tokens equal to two plus the number of cards named Goblin Gathering in your graveyard.

Far Wanderings

Search your library for a basic land card, put that card onto the battlefield tapped, then shuffle.
Threshold — If seven or more cards are in your graveyard, instead search your library for up to three basic land cards, put them onto the battlefield tapped, then shuffle.

Unexpected Windfall

Guttural Response

Surge to Victory

Exile target instant or sorcery card from your graveyard. Creatures you control get +X/+0 until end of turn, where X is that card's mana value. Whenever a creature you control deals combat damage to a player this turn, copy the exiled card. You may cast the copy without paying its mana cost.

Temple of the False God

{T}: Add {C}{C}. Activate only if you control five or more lands.

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.

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.")

Demand Answers

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

Arcane Signet

Goblin Matron

When Goblin Matron enters, you may search your library for a Goblin card, reveal that card, put it into your hand, then shuffle.

Tempt with Discovery

Tempting offer — Search your library for a land card and put it onto the battlefield. Each opponent may search their library for a land card and put it onto the battlefield. For each opponent who searches a library this way, search your library for a land card and put it onto the battlefield. Then each player who searched a library this way shuffles.

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.

Farseek

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

Gruul Signet

Krenko's Command

Create two 1/1 red Goblin creature tokens.

Rampant Growth

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

Empty the Warrens

Create two 1/1 red Goblin creature tokens.
Storm (When you cast this spell, copy it for each spell cast before it this turn.)

Sol Ring

Mizzix's Mastery

Exile target card that's an instant or sorcery from your graveyard. For each card exiled this way, copy it, and you may cast the copy without paying its mana cost. Exile Mizzix's Mastery.
Overload {5}{R}{R}{R} (You may cast this spell for its overload cost. If you do, change "target" in its text to "each.")

Mountain

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.

Liquimetal Torque

{T}: Add {C}.
{T}: Target nonland permanent becomes an artifact in addition to its other types until end of turn.

Impact Tremors

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

Overmaster

The next instant or sorcery spell you cast this turn can't be countered.
Draw a card.

Wort, the Raidmother

When Wort, the Raidmother enters, create two 1/1 red and green Goblin Warrior creature tokens.
Each red or green instant or sorcery spell you cast has conspire. (As you cast the spell, you may tap two untapped creatures you control that share a color with it. When you do, copy it and you may choose new targets for the copy.)

Past in Flames

Each instant and sorcery card in your graveyard gains flashback until end of turn. The flashback cost is equal to its mana cost.
Flashback {4}{R} (You may cast this card from your graveyard for its flashback cost. Then exile it.)

Mystic Peak

As Mystic Peak enters, you may pay 3 life. If you don't, it enters tapped.
{T}: Add {R}.

Pinnacle Monk

Prowess (Whenever you cast a noncreature spell, this creature gets +1/+1 until end of turn.)
When Pinnacle Monk enters, return target instant or sorcery card from your graveyard to your hand.

Pinnacle Monk // Mystic Peak

Oliphaunt

Trample
Whenever Oliphaunt attacks, another target creature you control gets +2/+0 and gains trample until end of turn.
Mountaincycling {1} ({1}, Discard this card: Search your library for a Mountain card, reveal it, put it into your hand, then shuffle.)

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.

Gamble

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

Increasing Vengeance

Copy target instant or sorcery spell you control. If this spell was cast from a graveyard, copy that spell twice instead. You may choose new targets for the copies.
Flashback {3}{R}{R} (You may cast this card from your graveyard for its flashback cost. Then exile it.)

Guttersnipe

Whenever you cast an instant or sorcery spell, this creature deals 2 damage to each opponent.

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.

Blasphemous Act

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

Siege-Gang Commander

When Siege-Gang Commander enters, create three 1/1 red Goblin creature tokens.
{1}{R}, Sacrifice a Goblin: Siege-Gang Commander deals 2 damage to any target.

Brass's Bounty

For each land you control, create a Treasure token. (It's an artifact with "{T}, Sacrifice this token: Add one mana of any color.")

Mana Geyser

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

Fireball

This spell costs {1} more to cast for each target beyond the first.
Fireball deals X damage divided evenly, rounded down, among any number of targets.

Reverberate

Copy target instant or sorcery spell. You may choose new targets for the copy.

Avoid Fate

Counter target instant or Aura spell that targets a permanent you control.

Sazacap's Brew

Gift a tapped Fish (You may promise an opponent a gift as you cast this spell. If you do, they create a tapped 1/1 blue Fish creature token before its other effects.)
As an additional cost to cast this spell, discard a card.
Target player draws two cards. If the gift was promised, target creature you control gets +2/+0 until end of turn.

Visions of Ruin

Each opponent sacrifices an artifact. For each artifact sacrificed this way, you create a Treasure token.
Flashback {8}{R}{R}. This spell costs {X} less to cast this way, where X is the greatest mana value of a commander you own on the battlefield or in the command zone. (You may cast this card from your graveyard for its flashback cost. Then exile it.)