Stormcatch Mentor

Haste
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.

Conduit Pylons

When Conduit Pylons enters, surveil 1. (Look at the top card of your library. You may put it into your graveyard.)
{T}: Add {C}.
{1}, {T}: Add one mana of any color.

Valley Floodcaller

Flash
You may cast noncreature spells as though they had flash.
Whenever you cast a noncreature spell, Birds, Frogs, Otters, and Rats you control get +1/+1 until end of turn. Untap them.

Quicksilver Dagger

Enchant creature
Enchanted creature has "{T}: This creature deals 1 damage to target player or planeswalker. You draw a card."

Hidden Cataract

Hidden Cataract enters tapped.
{T}: Add {U}.
{4}{U}, {T}, Sacrifice Hidden Cataract: Discover 4. Activate only as a sorcery. (Exile cards from the top of your library until you exile a nonland card with mana value 4 or less. Cast it without paying its mana cost or put it into your hand. Put the rest on the bottom in a random order.)

Impulse

Look at the top four cards of your library. Put one of them into your hand and the rest on the bottom of your library in any order.

Slickshot Show-Off

Flying, haste
Whenever you cast a noncreature spell, Slickshot Show-Off gets +2/+0 until end of turn.
Plot {1}{R} (You may pay {1}{R} and exile this card from your hand. Cast it as a sorcery on a later turn without paying its mana cost. Plot only as a sorcery.)

Teapot Slinger

Menace
Whenever you expend 4, Teapot Slinger deals 2 damage to each opponent. (You expend 4 as you spend your fourth total mana to cast spells during a turn.)

Strangle

Strangle deals 3 damage to target creature or planeswalker.

Lilah, Undefeated Slickshot

Prowess (Whenever you cast a noncreature spell, this creature gets +1/+1 until end of turn.)
Whenever you cast a multicolored instant or sorcery spell from your hand, exile that spell instead of putting it into your graveyard as it resolves. If you do, it becomes plotted. (You may cast it as a sorcery on a later turn without paying its mana cost.)

Mystic Sanctuary

({T}: Add {U}.)
Mystic Sanctuary enters tapped unless you control three or more other Islands.
When Mystic Sanctuary enters untapped, you may put target instant or sorcery card from your graveyard on top of your library.

Hidden Volcano

Hidden Volcano enters tapped.
{T}: Add {R}.
{4}{R}, {T}, Sacrifice Hidden Volcano: Discover 4. Activate only as a sorcery. (Exile cards from the top of your library until you exile a nonland card with mana value 4 or less. Cast it without paying its mana cost or put it into your hand. Put the rest on the bottom in a random order.)

Negate

Wishing Well

{T}: Put a coin counter on Wishing Well. When you do, you may cast target instant or sorcery card with mana value equal to the number of coin counters on Wishing Well from your graveyard without paying its mana cost. If that spell would be put into your graveyard, exile it instead. Activate only as a sorcery.

Imodane, the Pyrohammer

Whenever an instant or sorcery spell you control that targets only a single creature deals damage to that creature, Imodane deals that much damage to each opponent.

Channeled Force

As an additional cost to cast this spell, discard X cards.
Target player draws X cards. Channeled Force deals X damage to up to one target creature or planeswalker.

Unruly Catapult

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

Explosive Derailment

Spree (Choose one or more additional costs.)
+ {2} — Explosive Derailment deals 4 damage to target creature.
+ {2} — Destroy target artifact.

Slick Sequence

Slick Sequence deals 2 damage to any target. If you've cast another spell this turn, draw a card.

Sawblade Scamp

Haste
Whenever you cast a noncreature spell, put an oil counter on Sawblade Scamp.
{T}, Remove an oil counter from Sawblade Scamp: It deals 1 damage to each opponent.

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.

Edgewall Inn

Edgewall Inn enters tapped.
As Edgewall Inn enters, choose a color.
{T}: Add one mana of the chosen color.
{3}, {T}, Sacrifice Edgewall Inn: Return target card that has an Adventure from your graveyard to your hand.

Hypothesizzle

Draw two cards. Then you may discard a nonland card. When you do, Hypothesizzle deals 4 damage to target creature.

Commander's Sphere

{T}: Add one mana of any color in your commander's color identity.
Sacrifice Commander's Sphere: Draw a card.

Pyroceratops

Trample
Whenever you cast a noncreature spell, put a +1/+1 counter on Pyroceratops.

Guttersnipe

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

Rodeo Pyromancers

Whenever you cast your first spell each turn, add {R}{R}.

Island

Tempest Angler

Whenever you cast a noncreature spell, put a +1/+1 counter on Tempest Angler.

Shock

Essence Scatter

Ral, Crackling Wit

Whenever you cast a noncreature spell, put a loyalty counter on Ral, Crackling Wit.
+1: Create a 1/1 blue and red Otter creature token with prowess.
−3: Draw three cards, then discard two cards.
−10: Draw three cards. You get an emblem with "Instant and sorcery spells you cast have storm." (Whenever you cast an instant or sorcery spell, copy it for each spell cast before it this turn.)

Brain in a Jar

{1}, {T}: Put a charge counter on Brain in a Jar, then you may cast an instant or sorcery spell with mana value equal to the number of charge counters on Brain in a Jar from your hand without paying its mana cost.
{3}, {T}, Remove X charge counters from Brain in a Jar: Scry X.

Ral, Storm Conduit

Whenever you cast or copy an instant or sorcery spell, Ral, Storm Conduit deals 1 damage to target opponent or planeswalker.
+2: Scry 1.
−2: When you next cast an instant or sorcery spell this turn, copy that spell. You may choose new targets for the copy.

Refraction Elemental

Ward—Pay 2 life.
Whenever you cast a spell, Refraction Elemental deals 2 damage to each opponent.

Invasion of Karsus

(As a Siege enters, choose an opponent to protect it. You and others can attack it. When it's defeated, exile it, then cast it transformed.)
When Invasion of Karsus enters, it deals 3 damage to each creature and each planeswalker.

Invasion of Karsus // Refraction Elemental

Spreading Insurrection

Gain control of target creature you don't control until end of turn. Untap that creature. It gains haste until end of turn.
Storm (When you cast this spell, copy it for each spell cast before it this turn. You may choose new targets for the copies.)

Chandra, Hope's Beacon

Whenever you cast an instant or sorcery spell, copy it. You may choose new targets for the copy. This ability triggers only once each turn.
+2: Add two mana in any combination of colors.
+1: Exile the top five cards of your library. Until the end of your next turn, you may cast an instant or sorcery spell from among those exiled cards.
−X: Chandra, Hope's Beacon deals X damage to each of up to two targets.

Syr Carah, the Bold

Whenever Syr Carah, the Bold or an instant or sorcery spell you control deals damage to a player, exile the top card of your library. You may play that card this turn.
{T}: Syr Carah deals 1 damage to any target.

Wavebreak Hippocamp

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

Deny Existence

Counter target creature spell. If that spell is countered this way, exile it instead of putting it into its owner's graveyard.

Annul

Counter target artifact or enchantment spell.

Deny the Divine

Counter target creature or enchantment spell. If that spell is countered this way, exile it instead of putting it into its owner's graveyard.

Mountain

Scorching Shot

Scorching Shot deals 5 damage to target creature.

Izzet Staticaster

Flash (You may cast this spell any time you could cast an instant.)
Haste
{T}: Izzet Staticaster deals 1 damage to target creature and each other creature with the same name as that creature.

Nivmagus Elemental

Exile an instant or sorcery spell you control: Put two +1/+1 counters on Nivmagus Elemental. (That spell won't resolve.)

Niblis of Dusk

Flying
Prowess (Whenever you cast a noncreature spell, this creature gets +1/+1 until end of turn.)

Arcane Signet

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

Rockslide Sorcerer

Whenever you cast an instant, sorcery, or Wizard spell, Rockslide Sorcerer deals 1 damage to any target.

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.

Highland Lake

Highland Lake enters tapped.
{T}: Add {U} or {R}.

Electrodominance

Electrodominance deals X damage to any target. You may cast a spell with mana value X or less from your hand without paying its mana cost.

Improbable Alliance

Whenever you draw your second card each turn, create a 1/1 blue Faerie creature token with flying.
{4}{U}{R}: Draw a card, then discard a card.

Leyline of Anticipation

If Leyline of Anticipation is in your opening hand, you may begin the game with it on the battlefield.
You may cast spells as though they had flash.

Dreamstalker Manticore

Whenever you cast your first spell during each opponent's turn, Dreamstalker Manticore deals 1 damage to any target.

Blisterspit Gremlin

{1}, {T}: Blisterspit Gremlin deals 1 damage to each opponent.
Whenever you cast a noncreature spell, untap Blisterspit Gremlin.

Otterball Antics

Create a 1/1 blue and red Otter creature token with prowess. If this spell was cast from anywhere other than your hand, put a +1/+1 counter on that creature. (Whenever you cast a noncreature spell, a creature with prowess gets +1/+1 until end of turn.)
Flashback {3}{U} (You may cast this card from your graveyard for its flashback cost. Then exile it.)

Coruscation Mage

Offspring {2} (You may pay an additional {2} as you cast this spell. If you do, when this creature enters, create a 1/1 token copy of it.)
Whenever you cast a noncreature spell, this creature deals 1 damage to each opponent.

Mocking Sprite

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

Arena Trickster

Whenever you cast your first spell during each opponent's turn, put a +1/+1 counter on Arena Trickster.

Mind Stone

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

Hearthborn Battler

Haste
Whenever a player casts their second spell each turn, Hearthborn Battler deals 2 damage to target opponent.

Razzle-Dazzler

Whenever you cast your second spell each turn, put a +1/+1 counter on Razzle-Dazzler. It can't be blocked this turn.

Thunder Salvo

Thunder Salvo deals X damage to target creature, where X is 2 plus the number of other spells you've cast this turn.

Fblthp, Lost on the Range

Ward {2}
You may look at the top card of your library any time.
The top card of your library has plot. The plot cost is equal to its mana cost.
You may plot nonland cards from the top of your library.

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.

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.

Kraum, Violent Cacophony

Flying
Whenever you cast your second spell each turn, put a +1/+1 counter on Kraum, Violent Cacophony and draw a card.

Archaeomancer

When Archaeomancer enters, return target instant or sorcery card from your graveyard to your hand.

Sprite Dragon

Flying, haste
Whenever you cast a noncreature spell, put a +1/+1 counter on Sprite Dragon.