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.)

Mercurial Spelldancer

Mercurial Spelldancer can't be blocked.
Whenever you cast a noncreature spell, put an oil counter on Mercurial Spelldancer.
Whenever Mercurial Spelldancer deals combat damage to a player, you may remove two oil counters from it. If you do, when you next cast an instant or sorcery spell this turn, copy that spell. You may choose new targets for the copy.

Consider

Surveil 1. (Look at the top card of your library. You may put it into your graveyard.)
Draw a card.

Thought Scour

Target player mills two cards.
Draw a card.

Saheeli, Sublime Artificer

Whenever you cast a noncreature spell, create a 1/1 colorless Servo artifact creature token.
−2: Target artifact you control becomes a copy of another target artifact or creature you control until end of turn, except it's an artifact in addition to its other types.

Arcane Signet

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

Shadow Rift

Target creature gains shadow until end of turn. (It can block or be blocked by only creatures with shadow.)
Draw a card.

Harnfel, Horn of Bounty

Discard a card: Exile the top two cards of your library. You may play those cards this turn.

Birgi, God of Storytelling

Whenever you cast a spell, add {R}. Until end of turn, you don't lose this mana as steps and phases end.
Creatures you control can boast twice during each of your turns rather than once.

Birgi, God of Storytelling // Harnfel, Horn of Bounty

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}.

Will, Scholar of Frost

Instant and sorcery spells you cast cost {1} less to cast.
+1: Up to one target creature has base power and toughness 0/2 until your next turn.
−3: Draw two cards.
−7: Exile up to five target permanents. For each permanent exiled this way, its controller creates a 4/4 blue and red Elemental creature token.

Rowan, Scholar of Sparks

Instant and sorcery spells you cast cost {1} less to cast.
+1: Rowan, Scholar of Sparks deals 1 damage to each opponent. If you've drawn three or more cards this turn, she deals 3 damage to each opponent instead.
−4: You get an emblem with "Whenever you cast an instant or sorcery spell, you may pay {2}. If you do, copy that spell. You may choose new targets for the copy."

Rowan, Scholar of Sparks // Will, Scholar of Frost

Reinterpret

Counter target spell. You may cast a spell with an equal or lesser mana value from your hand without paying its mana cost.

Overmaster

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

Dig Through Time

Delve (Each card you exile from your graveyard while casting this spell pays for {1}.)
Look at the top seven cards of your library. Put two of them into your hand and the rest on the bottom of your library in any order.

Fists of Flame

Draw a card. Until end of turn, target creature gains trample and gets +1/+0 for each card you've drawn this turn.

Goblin Electromancer

Instant and sorcery spells you cast cost {1} less to cast.

Crimson Wisps

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

Jace's Sanctum

Instant and sorcery spells you cast cost {1} less to cast.
Whenever you cast an instant or sorcery spell, scry 1. (Look at the top card of your library. You may put that card on the bottom of your library.)

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.

Forgotten Cave

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

Serum Visions

Young Pyromancer

Whenever you cast an instant or sorcery spell, create a 1/1 red Elemental creature token.

Accelerate

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

Voracious Reader

Prowess (Whenever you cast a noncreature spell, this creature gets +1/+1 until end of turn.)
Instant and sorcery spells you cast cost {1} less to cast.

Curious Homunculus

{T}: Add {C}. Spend this mana only to cast an instant or sorcery spell.
At the beginning of your upkeep, if there are three or more instant and/or sorcery cards in your graveyard, transform Curious Homunculus.

Curious Homunculus // Voracious Reader

Kessig Flamebreather

Whenever you cast a noncreature spell, Kessig Flamebreather deals 1 damage to each opponent.

Mind's Desire

Shuffle your library. Then exile the top card of your library. Until end of turn, you may play that card without paying its mana cost.
Storm (When you cast this spell, copy it for each spell cast before it this turn.)

Temple of Epiphany

Temple of Epiphany enters the battlefield tapped.
When Temple of Epiphany enters the battlefield, scry 1.
{T}: Add {U} or {R}.

Thousand-Year Storm

Whenever you cast an instant or sorcery spell, copy it for each other instant and sorcery spell you've cast before it this turn. You may choose new targets for the copies.

Expedite

Explosion

Explosion deals X damage to any target. Target player draws X cards.

Expansion

Copy target instant or sorcery spell with mana value 4 or less. You may choose new targets for the copy.

Expansion // Explosion

Balmor, Battlemage Captain

Flying
Whenever you cast an instant or sorcery spell, creatures you control get +1/+0 and gain trample until end of turn.

Reach Through Mists

Aria of Flame

When Aria of Flame enters the battlefield, each opponent gains 10 life.
Whenever you cast an instant or sorcery spell, put a verse counter on Aria of Flame, then it deals damage equal to the number of verse counters on it to target player or planeswalker.

Baral, Chief of Compliance

Instant and sorcery spells you cast cost {1} less to cast.
Whenever a spell or ability you control counters a spell, you may draw a card. If you do, discard a card.

Narset's Reversal

Copy target instant or sorcery spell, then return it to its owner's hand. You may choose new targets for the copy.

Twinflame

Strive — This spell costs {2}{R} more to cast for each target beyond the first.
Choose any number of target creatures you control. For each of them, create a token that's a copy of that creature, except it has haste. Exile those tokens at the beginning of the next end step.

Blasphemous Act

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

Cerebral Vortex

Target player draws two cards, then Cerebral Vortex deals damage to that player equal to the number of cards they've drawn this turn.

Sleight of Hand

Look at the top two cards of your library. Put one of them into your hand and the other on the bottom of your library.

Guttersnipe

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

Haughty Djinn

Flying
Haughty Djinn's power is equal to the number of instant and sorcery cards in your graveyard.
Instant and sorcery spells you cast cost {1} less to cast.

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.)

Battle Hymn

Ghostly Flicker

Exile two target artifacts, creatures, and/or lands you control, then return those cards to the battlefield under your control.

Stream of Unconsciousness

Target creature gets -4/-0 until end of turn. If you control a Wizard, draw a card.

Firebrand Archer

Whenever you cast a noncreature spell, Firebrand Archer deals 1 damage to each opponent.

Rile

Rile deals 1 damage to target creature you control. That creature gains trample until end of turn.
Draw a card.

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.

Adeliz, the Cinder Wind

Flying, haste
Whenever you cast an instant or sorcery spell, Wizards you control get +1/+1 until end of turn.

Cleansing Wildfire

Destroy target land. Its controller may search their library for a basic land card, put it onto the battlefield tapped, then shuffle.
Draw a card.

Cathartic Reunion

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

Repeal

Return target nonland permanent with mana value X to its owner's hand.
Draw a card.

Step Through

Return two target creatures to their owners' hands.
Wizardcycling {2} ({2}, Discard this card: Search your library for a Wizard card, reveal it, put it into your hand, then shuffle.)

Reverberate

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

Imperial Recruiter

When Imperial Recruiter enters the battlefield, search your library for a creature card with power 2 or less, reveal it, put it into your hand, then shuffle.

Radiant Performer

Flash
When Radiant Performer enters the battlefield, if you cast it from your hand, choose target spell or ability that targets only a single permanent or player. Copy that spell or ability for each other permanent or player the spell or ability could target. Each copy targets a different one of those permanents and players.

Chilling Trap

Curiosity

Enchant creature
Whenever enchanted creature deals damage to an opponent, you may draw a card.

Cerulean Wisps

Target creature becomes blue until end of turn. Untap that creature.
Draw a card.

Fire

Fire deals 2 damage divided as you choose among one or two targets.

Fire // Ice

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.

Inaction Injunction

Detain target creature an opponent controls. (Until your next turn, that creature can't attack or block and its activated abilities can't be activated.)
Draw a card.

Lonely Sandbar

Lonely Sandbar enters the battlefield tapped.
{T}: Add {U}.
Cycling {U} ({U}, Discard this card: Draw a card.)

Talrand, Sky Summoner

Whenever you cast an instant or sorcery spell, create a 2/2 blue Drake creature token with flying.

Beamsplitter Mage

Whenever you cast an instant or sorcery spell that targets only Beamsplitter Mage, if you control one or more other creatures that spell could target, choose one of those creatures. Copy that spell. The copy targets the chosen creature.

Swiftfoot Boots

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

Prologue to Phyresis

Each opponent gets a poison counter.
Draw a card.

Frantic Search

Draw two cards, then discard two cards. Untap up to three lands.

Renegade Tactics

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

Mindsplice Apparatus

Flash
At the beginning of your upkeep, put an oil counter on Mindsplice Apparatus.
Instant and sorcery spells you cast cost {1} less to cast for each oil counter on Mindsplice Apparatus.

Psychotic Fury

Target multicolored creature gains double strike until end of turn.
Draw a card.

Path of Ancestry

Path of Ancestry enters the battlefield tapped.
{T}: Add one mana of any color in your commander's color identity. When that mana is spent to cast a creature spell that shares a creature type with your commander, scry 1. (Look at the top card of your library. You may put that card on the bottom.)

Ashmouth Dragon

Flying
Whenever you cast an instant or sorcery spell, Ashmouth Dragon deals 2 damage to any target.

Smoldering Egg

Defender
Whenever you cast an instant or sorcery spell, put a number of ember counters on Smoldering Egg equal to the amount of mana spent to cast that spell. Then if Smoldering Egg has seven or more ember counters on it, remove them and transform Smoldering Egg.

Smoldering Egg // Ashmouth Dragon

Sorcerous Sight

Look at target opponent's hand.
Draw a card.

Valakut Stoneforge

Valakut Stoneforge enters the battlefield 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

Shivan Reef

{T}: Add {C}.
{T}: Add {U} or {R}. Shivan Reef deals 1 damage to you.

Command Tower

Talisman of Creativity

{T}: Add {C}.
{T}: Add {U} or {R}. Talisman of Creativity deals 1 damage to you.

Brass's Bounty

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

Treasure Cruise

Delve (Each card you exile from your graveyard while casting this spell pays for {1}.)
Draw three cards.

Rewind

Counter target spell. Untap up to four lands.

Ancestral Anger

Target creature gains trample and gets +X/+0 until end of turn, where X is 1 plus the number of cards named Ancestral Anger in your graveyard.
Draw a card.

Slip Through Space

Devoid (This card has no color.)
Target creature can't be blocked this turn.
Draw a card.

Think Twice

Draw a card.
Flashback {2}{U} (You may cast this card from your graveyard for its flashback cost. Then exile it.)

Radical Idea

Draw a card.
Jump-start (You may cast this card from your graveyard by discarding a card in addition to paying its other costs. Then exile this card.)

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.")

Prismari Command

Choose two —
• Prismari Command deals 2 damage to any target.
• Target player draws two cards, then discards two cards.
• Target player creates a Treasure token.
• Destroy target artifact.

Metallurgic Summonings

Whenever you cast an instant or sorcery spell, create an X/X colorless Construct artifact creature token, where X is that spell's mana value.
{3}{U}{U}, Exile Metallurgic Summonings: Return all instant and sorcery cards from your graveyard to your hand. Activate only if you control six or more artifacts.

Reliquary Tower

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

Thought Vessel

Expressive Iteration

Look at the top three cards of your library. Put one of them into your hand, put one of them on the bottom of your library, and exile one of them. You may play the exiled card this turn.

Twisted Image

Switch target creature's power and toughness until end of turn.
Draw a card.

Pyretic Ritual

Silundi Isle

Silundi Isle enters the battlefield tapped.
{T}: Add {U}.

Silundi Vision

Look at the top six cards of your library. You may reveal an instant or sorcery card from among them and put it into your hand. Put the rest on the bottom of your library in a random order.