Fellwar Stone

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

Expedite

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

Goblin Lore

Draw four cards, then discard three cards at random.

Boiling Blood

Target creature attacks this turn if able.
Draw a card.

Burning Inquiry

Each player draws three cards, then discards three cards at random.

Sol Ring

Renegade Tactics

Target creature can't block this turn.
Draw a card.

Runaway Steam-Kin

Whenever you cast a red spell, if Runaway Steam-Kin has fewer than three +1/+1 counters on it, put a +1/+1 counter on Runaway Steam-Kin.
Remove three +1/+1 counters from Runaway Steam-Kin: Add {R}{R}{R}.

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.)

Ashnod's Altar

Seething Song

Accelerate

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.)

Magmatic Insight

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

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.

Transmogrify

Exile target creature. That creature's controller reveals cards from the top of their library until they reveal a creature card. That player puts that card onto the battlefield, then shuffles the rest into their library.

Divergent Transformations

Undaunted (This spell costs {1} less to cast for each opponent.)
Exile two target creatures. For each of those creatures, its controller reveals cards from the top of their library until they reveal a creature card, puts that card onto the battlefield, then shuffles the rest into their library.

Arcane Signet

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

Shifting Shadow

Enchant creature
Enchanted creature has haste and "At the beginning of your upkeep, destroy this creature. Reveal cards from the top of your library until you reveal a creature card. Put that card onto the battlefield and attach Shifting Shadow to it, then put all other cards revealed this way on the bottom of your library in a random order."

Ruby Medallion

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

Stun

Goblin Bombardment

Sacrifice a creature: Goblin Bombardment deals 1 damage to any target.

Underworld Breach

Each nonland card in your graveyard has escape. The escape cost is equal to the card's mana cost plus exile three other cards from your graveyard. (You may cast cards from your graveyard for their escape cost.)
At the beginning of the end step, sacrifice Underworld Breach.

Thrill of Possibility

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

Squee, the Immortal

You may cast Squee, the Immortal from your graveyard or from exile.

Pyretic Ritual

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.)

Crash Through

Creatures you control gain trample until end of turn. (Each of those creature can deal excess combat damage to the player or planeswalker it's attacking.)
Draw a card.

Warlord's Fury

Creatures you control gain first strike until end of turn.
Draw a card.

Reforge the Soul

Each player discards their hand, then draws seven cards.
Miracle {1}{R} (You may cast this card for its miracle cost when you draw it if it's the first card you drew this turn.)

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.

Fire Diamond

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

Tormenting Voice

Bonus Round

Until end of turn, whenever a player casts an instant or sorcery spell, that player copies it and may choose new targets for the copy.

Mountain

Overmaster

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

Caged Sun

As Caged Sun enters, choose a color.
Creatures you control of the chosen color get +1/+1.
Whenever a land's ability causes you to add one or more mana of the chosen color, add one additional mana of that color.

Mana Geyser

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

Cathartic Reunion

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

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.")

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.

Crimson Wisps

Target creature becomes red and gains haste until end of turn. (It can attack and {T} this turn.)
Draw a card.

Gamble

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