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}.

Wavebreak Hippocamp

Whenever you cast your first spell during each opponent's turn, draw a card.

Ionize

Counter target spell. Ionize deals 2 damage to that spell's controller.

Quicken

The next sorcery spell you cast this turn can be cast as though it had flash. (It can be cast any time you could cast an instant.)
Draw a card.

Arcane Signet

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

Izzet Boilerworks

Izzet Boilerworks enters the battlefield tapped.
When Izzet Boilerworks enters the battlefield, return a land you control to its owner's hand.
{T}: Add {U}{R}.

Wayfarer's Bauble

{2}, {T}, Sacrifice Wayfarer's Bauble: Search your library for a basic land card, put that card onto the battlefield tapped, then shuffle.

Veyran, Voice of Duality

Magecraft — Whenever you cast or copy an instant or sorcery spell, Veyran, Voice of Duality gets +1/+1 until end of turn.
If you casting or copying an instant or sorcery spell causes a triggered ability of a permanent you control to trigger, that ability triggers an additional time.

Firebrand Archer

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

Teach by Example

When you next cast an instant or sorcery spell this turn, copy that spell. You may choose new targets for the copy.

Guttersnipe

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

Fleeting Distraction

Target creature gets -1/-0 until end of turn.
Draw a card.

Portent

Look at the top three cards of target player's library, then put them back in any order. You may have that player shuffle.
Draw a card at the beginning of the next turn's upkeep.

Pongify

Destroy target creature. It can't be regenerated. Its controller creates a 3/3 green Ape creature token.

Niv-Mizzet, Parun

This spell can't be countered.
Flying
Whenever you draw a card, Niv-Mizzet, Parun deals 1 damage to any target.
Whenever a player casts an instant or sorcery spell, you draw a card.

Wizard's Retort

This spell costs {1} less to cast if you control a Wizard.
Counter target spell.

Electrostatic Field

Defender
Whenever you cast an instant or sorcery spell, Electrostatic Field deals 1 damage to each opponent.

Epic Experiment

Exile the top X cards of your library. You may cast instant and sorcery spells with mana value X or less from among them without paying their mana costs. Then put all cards exiled this way that weren't cast into your graveyard.

Command Tower

Brainstorm

Draw three cards, then put two cards from your hand on top of your library in any order.

Geistblast

Geistblast deals 2 damage to any target.
{2}{U}, Exile Geistblast from your graveyard: Copy target instant or sorcery spell you control. You may choose new targets for the copy.

Arcane Denial

Counter target spell. Its controller may draw up to two cards at the beginning of the next turn's upkeep.
You draw a card at the beginning of the next turn's upkeep.

Curse of the Swine

Exile X target creatures. For each creature exiled this way, its controller creates a 2/2 green Boar creature token.

Thrill of Possibility

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

Chilling Trap

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

Storm-Kiln Artist

Storm-Kiln Artist gets +1/+0 for each artifact you control.
Magecraft — Whenever you cast or copy an instant or sorcery spell, create a Treasure token.

Negate

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.

Seething Song

Temple of Epiphany

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

Gelectrode

{T}: Gelectrode deals 1 damage to any target.
Whenever you cast an instant or sorcery spell, you may untap Gelectrode.

By Force

Mana Geyser

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

Reliquary Tower

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

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.)

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.)

Thought Vessel

Shivan Reef

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

Thermo-Alchemist

Defender
{T}: Thermo-Alchemist deals 1 damage to each opponent.
Whenever you cast an instant or sorcery spell, untap Thermo-Alchemist.

Ponder

Look at the top three cards of your library, then put them back in any order. You may shuffle.
Draw a card.

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.

Archmage Emeritus

Magecraft — Whenever you cast or copy an instant or sorcery spell, draw a card.

Izzet Guildgate

Izzet Guildgate enters the battlefield tapped.
{T}: Add {U} or {R}.

Expedite

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

Preordain

Scry 2, then draw a card. (To scry 2, look at the top two cards of your library, then put any number of them on the bottom and the rest on top in any order.)

Blasphemous Act

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

Rionya, Fire Dancer

At the beginning of combat on your turn, create X tokens that are copies of another target creature you control, where X is one plus the number of instant and sorcery spells you've cast this turn. They gain haste. Exile them at the beginning of the next end step.

Izzet Signet

Dualcaster Mage

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

Krark, the Thumbless

Whenever you cast an instant or sorcery spell, flip a coin. If you lose the flip, return that spell to its owner's hand. If you win the flip, copy that spell, and you may choose new targets for the copy.
Partner (You can have two commanders if both have partner.)

Counterspell

Slip Through Space

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

Jori En, Ruin Diver

Whenever you cast your second spell each turn, draw a card.

Zada, Hedron Grinder

Whenever you cast an instant or sorcery spell that targets only Zada, Hedron Grinder, copy that spell for each other creature you control that the spell could target. Each copy targets a different one of those creatures.

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.

Treasure Cruise

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

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.

Sol Ring

Dissipation Field

Whenever a permanent deals damage to you, return it to its owner's hand.

Swiftwater Cliffs

Swiftwater Cliffs enters the battlefield tapped.
When Swiftwater Cliffs enters the battlefield, you gain 1 life.
{T}: Add {U} or {R}.

Renegade Tactics

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

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.

Cerulean Wisps

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

Rile

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

Twisted Image

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

Rootha, Mercurial Artist

{2}, Return Rootha, Mercurial Artist to its owner's hand: Copy target instant or sorcery spell you control. You may choose new targets for the copy.

Peek

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

Grapeshot

Grapeshot deals 1 damage to any target.
Storm (When you cast this spell, copy it for each spell cast before it this turn. You may choose new targets for the copies.)

Stream of Unconsciousness

Warlord's Fury

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

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.