Talrand, Sky Summoner

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

Foil

You may discard an Island card and another card rather than pay this spell's mana cost.
Counter target spell.

Arcane Signet

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

Chrome Host Seedshark

Flying
Whenever you cast a noncreature spell, incubate X, where X is that spell's mana value. (Create an Incubator token with X +1/+1 counters on it and "{2}: Transform this artifact." It transforms into a 0/0 Phyrexian artifact creature.)

Island

Curse of the Swine

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

Everflowing Chalice

Multikicker {2} (You may pay an additional {2} any number of times as you cast this spell.)
Everflowing Chalice enters the battlefield with a charge counter on it for each time it was kicked.
{T}: Add {C} for each charge counter on Everflowing Chalice.

Transcendent Message

Convoke (Your creatures can help cast this spell. Each creature you tap while casting this spell pays for {1} or one mana of that creature's color.)
Draw X cards.

Codex Shredder

{T}: Target player mills a card. (They put the top card of their library into their graveyard.)
{5}, {T}, Sacrifice Codex Shredder: Return target card from your graveyard to your hand.

Gale, Waterdeep Prodigy

Whenever you cast an instant or sorcery spell from your hand, you may cast up to one target card of the other type from your graveyard. If a spell cast from your graveyard this way would be put into your graveyard, exile it instead.
Choose a Background (You can have a Background as a second commander.)

Plant Tadpoles

Tap X target creatures. They don't untap during their controllers' next untap steps. (Then exile this card. You may cast the creature later from exile.)

Illithid Harvester

Ceremorphosis — When Illithid Harvester enters the battlefield, turn any number of target tapped nontoken creatures face down. They're 2/2 Horror creatures.

Illithid Harvester // Plant Tadpoles

Reality Shift

Exile target creature. Its controller manifests the top card of their library. (That player puts the top card of their library onto the battlefield face down as a 2/2 creature. If it's a creature card, it can be turned face up any time for its mana cost.)

Drowned Secrets

Whenever you cast a blue spell, target player mills two cards.

Cone of Cold

Roll a d20.
1—9 | Tap all creatures your opponents control.
10—19 | Tap all creatures your opponents control. Those creatures don't untap during their controllers' next untap steps.
20 | Tap all creatures your opponents control. Those creatures don't untap during their controllers' next untap steps. Until your next turn, creatures your opponents control enter the battlefield tapped.

Myriad Landscape

Myriad Landscape enters the battlefield tapped.
{T}: Add {C}.
{2}, {T}, Sacrifice Myriad Landscape: Search your library for up to two basic land cards that share a land type, put them onto the battlefield tapped, then shuffle.

Deep Analysis

Target player draws two cards.
Flashback—{1}{U}, Pay 3 life. (You may cast this card from your graveyard for its flashback cost. Then exile it.)

Venture Deeper

Target player mills four cards. (Then exile this card. You may cast the creature later from exile.)

Merfolk Secretkeeper

Merfolk Secretkeeper // Venture Deeper

Replication Technique

Demonstrate (When you cast this spell, you may copy it. If you do, choose an opponent to also copy it. Players may choose new targets for their copies.)
Create a token that's a copy of target permanent you control.

Looter il-Kor

Shadow (This creature can block or be blocked by only creatures with shadow.)
Whenever Looter il-Kor deals damage to an opponent, draw a card, then discard a card.

Invocation of the Founders

Whenever you cast an instant or sorcery spell from your hand, you may copy that spell. You may choose new targets for the copy.

Invasion of Arcavios

(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 Arcavios enters the battlefield, search your library, graveyard, and/or outside the game for an instant or sorcery card you own, reveal it, and put it into your hand. If you search your library this way, shuffle.

Invasion of Arcavios // Invocation of the Founders

Wonder

Flying
As long as Wonder is in your graveyard and you control an Island, creatures you control have flying.

Disdainful Stroke

Counter target spell with mana value 4 or greater.

Slip Through Space

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

Flow of Ideas

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.)

Occult Epiphany

Draw X cards, then discard X cards. Create a 1/1 white Spirit creature token with flying for each card type among cards discarded this way.

Decanter of Endless Water

You have no maximum hand size.
{T}: Add one mana of any color.

Tempted by the Oriq

For each opponent, gain control of up to one target creature or planeswalker that player controls with mana value 3 or less.

Winds of Rebuke

Return target nonland permanent to its owner's hand. Each player mills two cards.

Thought Scour

Target player mills two cards.
Draw a card.

Octavia, Living Thesis

This spell costs {8} less to cast if you have eight or more instant and/or sorcery cards in your graveyard.
Ward {8}
Magecraft — Whenever you cast or copy an instant or sorcery spell, target creature has base power and toughness 8/8 until end of turn.

Stolen by the Fae

Return target creature with mana value X to its owner's hand. You create X 1/1 blue Faerie creature tokens with flying.

Rise from the Tides

Create a tapped 2/2 black Zombie creature token for each instant and sorcery card in your graveyard.

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.

Silundi Vision // Silundi Isle

Pull from Tomorrow

High Tide

Until end of turn, whenever a player taps an Island for mana, that player adds an additional {U}.

Flow of Knowledge

Draw a card for each Island you control, then discard two cards.

Ghostly Pilferer

Whenever Ghostly Pilferer becomes untapped, you may pay {2}. If you do, draw a card.
Whenever an opponent casts a spell from anywhere other than their hand, draw a card.
Discard a card: Ghostly Pilferer can't be blocked this turn.

Turnabout

Choose artifact, creature, or land. Tap all untapped permanents of the chosen type target player controls, or untap all tapped permanents of that type that player controls.

Engulf the Shore

Return to their owners' hands all creatures with toughness less than or equal to the number of Islands you control.

Resculpt

Exile target artifact or creature. Its controller creates a 4/4 blue and red Elemental creature token.

Negate

Thirst for Discovery

Draw three cards. Then discard two cards unless you discard a basic land card.

Frantic Search

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

Boon of the Wish-Giver

Draw four cards.
Cycling {1} ({1}, Discard this card: Draw a card.)

Mind Stone

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

Spectral Deluge

Return each creature your opponents control with toughness X or less to its owner's hand, where X is the number of Islands you control.
Foretell {1}{U}{U} (During your turn, you may pay {2} and exile this card from your hand face down. Cast it on a later turn for its foretell cost.)

Beyeen Coast

Beyeen Coast enters the battlefield tapped.
{T}: Add {U}.

Beyeen Veil

Creatures your opponents control get -2/-0 until end of turn.

Beyeen Veil // Beyeen Coast

Elminster's Simulacrum

For each opponent, you create a token that's a copy of up to one target creature that player controls.

Deranged Assistant

{T}, Mill a card: Add {C}. (To mill a card, put the top card of your library into your graveyard.)

Hard Evidence

Create a 0/3 blue Crab creature token.
Investigate. (Create a Clue token. It's an artifact with "{2}, Sacrifice this artifact: Draw a card.")

Terrain Generator

{T}: Add {C}.
{2}, {T}: You may put a basic land card from your hand onto the battlefield tapped.

Murmuring Mystic

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

Fact or Fiction

Reveal the top five cards of your library. An opponent separates those cards into two piles. Put one pile into your hand and the other into your graveyard.

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.

Chemister's Insight

Draw two cards.
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.)

Compulsive Research

Target player draws three cards. Then that player discards two cards unless they discard a land card.

Champion of Wits

When Champion of Wits enters the battlefield, you may draw cards equal to its power. If you do, discard two cards.
Eternalize {5}{U}{U} ({5}{U}{U}, Exile this card from your graveyard: Create a token that's a copy of it, except it's a 4/4 black Zombie Snake Wizard with no mana cost. Eternalize only as a sorcery.)

Floodgate

Defender (This creature can't attack.)
When Floodgate has flying, sacrifice it.
When Floodgate leaves the battlefield, it deals damage equal to half the number of Islands you control, rounded down, to each nonblue creature without flying.

Snap

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

Dreamscape Artist

{2}{U}, {T}, Discard a card, Sacrifice a land: Search your library for up to two basic land cards, put them onto the battlefield, then shuffle.

Perpetual Timepiece

{T}: Mill two cards.
{2}, Exile Perpetual Timepiece: Shuffle any number of target cards from your graveyard into your library.

See Double

This spell can't be copied.
Choose one. If an opponent has eight or more cards in their graveyard, you may choose both.
• Copy target spell. You may choose new targets for the copy. (A copy of a permanent spell becomes a token.)
• Create a token that's a copy of target creature.

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.

Walking Atlas

{T}: You may put a land card from your hand onto the battlefield.

Scourge of Fleets

When Scourge of Fleets enters the battlefield, return each creature your opponents control with toughness X or less to its owner's hand, where X is the number of Islands you control.

Flash of Insight

Look at the top X cards of your library. Put one of them into your hand and the rest on the bottom of your library in any order.
Flashback—{1}{U}, Exile X blue cards from your graveyard. (You may cast this card from your graveyard for its flashback cost, then exile it. You can't exile Flash of Insight to pay for its own flashback cost.)

Callous Dismissal

Return target nonland permanent to its owner's hand.
Amass Zombies 1. (Put a +1/+1 counter on an Army you control. It's also a Zombie. If you don't control an Army, create a 0/0 black Zombie Army creature token first.)