Have

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.)

Getting

Glamdring

Equipped creature has first strike and gets +1/+0 for each instant and sorcery card in your graveyard.
Whenever equipped creature deals combat damage to a player, you may cast an instant or sorcery spell from your hand with mana value less than or equal to that damage without paying its mana cost.
Equip {3}

Shore Up

Target creature you control gets +1/+1 and gains hexproof until end of turn. Untap it. (It can't be the target of spells or abilities your opponents control.)

Alania's Pathmaker

When Alania's Pathmaker enters, exile the top card of your library. Until the end of your next turn, you may play that card.

Don't Have

Expedite

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

Blow Off Steam

Blow Off Steam deals 1 damage to any target. (Then exile this card. You may cast the creature later from exile.)

Frolicking Familiar

Flying
Whenever you cast an instant or sorcery spell, Frolicking Familiar gets +1/+1 until end of turn.

Frolicking Familiar // Blow Off Steam

Temur Battle Rage

Target creature gains double strike until end of turn.
Ferocious — That creature also gains trample until end of turn if you control a creature with power 4 or greater.

Combat Research

Enchant creature
Enchanted creature has "Whenever this creature deals combat damage to a player, draw a card."
As long as enchanted creature is legendary, it gets +1/+1 and has ward {1}. (Whenever enchanted creature becomes the target of a spell or ability an opponent controls, counter it unless that player pays {1}.)

Stormsplitter

Haste
Whenever you cast an instant or sorcery spell, create a token that's a copy of Stormsplitter. Exile that token at the beginning of the next end step.

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.

Talisman of Creativity

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

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.

Stormcarved Coast

Stormcarved Coast enters tapped unless you control two or more other lands.
{T}: Add {U} or {R}.

Sulfur Falls

Sulfur Falls enters tapped unless you control an Island or a Mountain.
{T}: Add {U} or {R}.

Snap

Return target creature to its owner's hand. Untap up to two lands.

Tempest Angler

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

Renegade Tactics

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

Stubborn Denial

Counter target noncreature spell unless its controller pays {1}.
Ferocious — If you control a creature with power 4 or greater, counter that spell instead.

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.

Harnesser of Storms

Whenever you cast a noncreature or Otter spell, you may exile the top card of your library. Until end of turn, you may play that card. This ability triggers only once each turn.

Shivan Reef

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

Path of Ancestry

Path of Ancestry enters 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.)

Thrill of Possibility

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

Great Train Heist

Spree (Choose one or more additional costs.)
+ {2}{R} — Untap all creatures you control. If it's your combat phase, there is an additional combat phase after this phase.
+ {2} — Creatures you control get +1/+0 and gain first strike until end of turn.
+ {R} — Choose target opponent. Whenever a creature you control deals combat damage to that player this turn, create a tapped Treasure token.

Haze of Rage

Buyback {2} (You may pay an additional {2} as you cast this spell. If you do, put this card into your hand as it resolves.)
Creatures you control get +1/+0 until end of turn.
Storm (When you cast this spell, copy it for each spell cast before it this turn.)

Distant Melody

Choose a creature type. Draw a card for each permanent you control of that type.

Kindlespark Duo

{T}: Kindlespark Duo deals 1 damage to target opponent.
Whenever you cast a noncreature spell, untap Kindlespark Duo.

Rewind

Counter target spell. Untap up to four lands.

Aqueous Form

Enchant creature
Enchanted creature can't be blocked.
Whenever enchanted creature attacks, scry 1. (Look at the top card of your library. You may put that card on the bottom.)

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.

Kasmina's Transmutation

Enchant creature
Enchanted creature loses all abilities and has base power and toughness 1/1.

Run Away Together

Choose two target creatures controlled by different players. Return those creatures to their owners' hands.

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.)

Pearl of Wisdom

This spell costs {1} less to cast if you control an Otter.
Draw two cards.

Serum Visions

Reverberate

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

Alania, Divergent Storm

Whenever you cast a spell, if it's the first instant spell, the first sorcery spell, or the first Otter spell other than Alania you've cast this turn, you may have target opponent draw a card. If you do, copy that spell. You may choose new targets for the copy.

Void Snare

Return target nonland permanent to its owner's hand.

Bident of Thassa

Whenever a creature you control deals combat damage to a player, you may draw a card.
{1}{U}, {T}: Creatures your opponents control attack this turn if able.

Cascade Bluffs

{T}: Add {C}.
{U/R}, {T}: Add {U}{U}, {U}{R}, or {R}{R}.

Island

Bria, Riptide Rogue

Prowess (Whenever you cast a noncreature spell, this creature gets +1/+1 until end of turn.)
Other creatures you control have prowess. (If a creature has multiple instances of prowess, each triggers separately.)
Whenever you cast a noncreature spell, target creature you control can't be blocked this turn.

Izzet Signet

Young Pyromancer

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

Abrade

Choose one —
• Abrade deals 3 damage to target creature.
• Destroy target artifact.

Warlord's Fury

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

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.

Frantic Search

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

Injury

Aftermath (Cast this spell only from your graveyard. Then exile it.)
Injury deals 2 damage to target creature and 2 damage to target player or planeswalker.

Insult

Damage can't be prevented this turn. If a source you control would deal damage this turn, it deals double that damage instead.

Insult // Injury

Frostboil Snarl

As Frostboil Snarl enters, you may reveal an Island or Mountain card from your hand. If you don't, Frostboil Snarl enters tapped.
{T}: Add {U} or {R}.

Thought Scour

Target player mills two cards.
Draw a card.

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.

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.

Water Wings

Until end of turn, target creature you control has base power and toughness 4/4 and gains flying and hexproof. (It can't be the target of spells or abilities your opponents control.)

Shark Typhoon

Whenever you cast a noncreature spell, create an X/X blue Shark creature token with flying, where X is that spell's mana value.
Cycling {X}{1}{U} ({X}{1}{U}, Discard this card: Draw a card.)
When you cycle Shark Typhoon, create an X/X blue Shark creature token with flying.

Stormchaser's Talent

(Gain the next level as a sorcery to add its ability.)
When Stormchaser's Talent enters, create a 1/1 blue and red Otter creature token with prowess.
{3}{U}: Level 2
When this Class becomes level 2, return target instant or sorcery card from your graveyard to your hand.
{5}{U}: Level 3
Whenever you cast an instant or sorcery spell, create a 1/1 blue and red Otter creature token with prowess.

Kitsa, Otterball Elite

Vigilance
Prowess (Whenever you cast a noncreature spell, this creature gets +1/+1 until end of turn.)
{T}: Draw a card, then discard a card.
{2}, {T}: Copy target instant or sorcery spell you control. You may choose new targets for the copy. Activate only if Kitsa's power is 3 or greater.

Pull from Tomorrow

Archmage Emeritus

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

Scry 1. (Look at the top card of your library. You may put that card on the bottom.)
Draw a card.

Murmuring Mystic

Whenever you cast an instant or sorcery spell, create a 1/1 blue Bird Illusion creature token with flying.

Arcane Signet

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

Harmonic Prodigy

Prowess (Whenever you cast a noncreature spell, this creature gets +1/+1 until end of turn.)
If an ability of a Shaman or another Wizard you control triggers, that ability triggers an additional time.

Dramatic Reversal

Untap all nonland permanents you control.

Command Tower

Mountain

Guttersnipe

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

Leap

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

Slip Out the Back

Put a +1/+1 counter on target creature. It phases out. (Treat it and anything attached to it as though they don't exist until its controller's next turn.)

Curiosity

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

Sol Ring

Lightshell Duo

Prowess (Whenever you cast a noncreature spell, this creature gets +1/+1 until end of turn.)
When this creature enters, surveil 2. (Look at the top two cards of your library, then put any number of them into your graveyard and the rest on top of your library in any order.)

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.

Demand Answers

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

Talrand, Sky Summoner

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