Access Denied

Counter target spell. Create X 1/1 colorless Thopter artifact creature tokens with flying, where X is that spell's mana value.

Future Sight

Play with the top card of your library revealed.
You may play lands and cast spells from the top of your library.

Floodgate

Defender
When Floodgate has flying, sacrifice it.
When Floodgate leaves the battlefield, it deals damage to each nonblue creature without flying equal to half the number of Islands you control, rounded down.

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.

Solemn Simulacrum

When Solemn Simulacrum enters, you may search your library for a basic land card, put that card onto the battlefield tapped, then shuffle.
When Solemn Simulacrum dies, you may draw a card.

Sublime Epiphany

Choose one or more —
• Counter target spell.
• Counter target activated or triggered ability.
• Return target nonland permanent to its owner's hand.
• Create a token that's a copy of target creature you control.
• Target player draws a card.

Supplant Form

Return target creature to its owner's hand. You create a token that's a copy of that creature.

Nexus of Fate

Take an extra turn after this one.
If Nexus of Fate would be put into a graveyard from anywhere, reveal Nexus of Fate and shuffle it into its owner's library instead.

Enter the Infinite

Draw cards equal to the number of cards in your library, then put a card from your hand on top of your library. You have no maximum hand size until your next turn.

Nykthos, Shrine to Nyx

{T}: Add {C}.
{2}, {T}: Choose a color. Add an amount of mana of that color equal to your devotion to that color. (Your devotion to a color is the number of mana symbols of that color in the mana costs of permanents you control.)

Roil Elemental

Flying
Landfall — Whenever a land you control enters, you may gain control of target creature for as long as you control Roil Elemental.

Stroke of Genius

Thassa's Oracle

When Thassa's Oracle enters, look at the top X cards of your library, where X is your devotion to blue. Put up to one of them on top of your library and the rest on the bottom of your library in a random order. If X is greater than or equal to the number of cards in your library, you win the game. (Each {U} in the mana costs of permanents you control counts toward your devotion to blue.)

Essence Flux

Exile target creature you control, then return that card to the battlefield under its owner's control. If it's a Spirit, put a +1/+1 counter on it.

Archmage's Charm

Choose one —
• Counter target spell.
• Target player draws two cards.
• Gain control of target nonland permanent with mana value 1 or less.

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.

Reliquary Tower

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

Thunderclap Drake

Flying
Instant and sorcery spells you cast cost {1} less to cast.
{2}{U}, Sacrifice Thunderclap Drake: When you next cast an instant or sorcery spell this turn, copy it for each time you've cast your commander from the command zone this game. You may choose new targets for the copies.

Mind Stone

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

Silver Scrutiny

You may cast Silver Scrutiny as though it had flash if X is 3 or less.
Draw X cards.

Hour of Eternity

Exile X target creature cards from your graveyard. For each card exiled this way, create a token that's a copy of that card, except it's a 4/4 black Zombie.

Pull from Tomorrow

Scourge of Fleets

When Scourge of Fleets enters, 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.

Rapid Hybridization

Destroy target creature. It can't be regenerated. That creature's controller creates a 3/3 green Frog Lizard creature token.

Energy Flux

All artifacts have "At the beginning of your upkeep, sacrifice this artifact unless you pay {2}."

Unfathomable Truths

Devoid (This card has no color.)
Draw three cards and create a 0/1 colorless Eldrazi Spawn creature token with "Sacrifice this creature: Add {C}."

Body of Knowledge

Body of Knowledge's power and toughness are each equal to the number of cards in your hand.
You have no maximum hand size.
Whenever Body of Knowledge is dealt damage, draw that many cards.

Sapphire Medallion

Blue spells you cast cost {1} less to cast.

Even the Score

This spell costs {U}{U}{U} less to cast if an opponent has drawn four or more cards this turn.
Draw X cards.

Loyal Drake

Flying
Lieutenant — At the beginning of combat on your turn, if you control your commander, draw a card.

Harbinger of the Seas

Nanogene Conversion

Choose target creature you control. Each other creature becomes a copy of that creature until end of turn, except it isn't legendary.

Blue Sun's Zenith

Target player draws X cards. Shuffle Blue Sun's Zenith into its owner's library.

Jin-Gitaxias, Progress Tyrant

Whenever you cast an artifact, instant, or sorcery spell, copy that spell. You may choose new targets for the copy. This ability triggers only once each turn. (A copy of a permanent spell becomes a token.)
Whenever an opponent casts an artifact, instant, or sorcery spell, counter that spell. This ability triggers only once each turn.

The Flood of Mars

Islandwalk (This creature can't be blocked as long as defending player controls an Island.)
Water Always Wins — Whenever The Flood of Mars attacks, put a flood counter on another target creature or land. If it's a creature, it becomes a copy of The Flood of Mars. If it's a land, it becomes an Island in addition to its other types.

Desynchronization

Return each nonland permanent that's not historic to its owner's hand. (Artifacts, legendaries, and Sagas are historic.)

Engulf the Shore

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

Island

Caged Sun

As Caged Sun enters, choose a color.
Creatures you control of the chosen color get +1/+1.
Whenever a land's ability causes you to add one or more mana of the chosen color, add one additional mana of that color.

Elminster's Simulacrum

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

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.

Rite of Replication

Kicker {5} (You may pay an additional {5} as you cast this spell.)
Create a token that's a copy of target creature. If this spell was kicked, create five of those tokens instead.

Gather Specimens

If a creature would enter the battlefield under an opponent's control this turn, it enters under your control instead.

Fabricate

Search your library for an artifact card, reveal it, put it into your hand, then shuffle.

Beacon of Tomorrows

Target player takes an extra turn after this one. Shuffle Beacon of Tomorrows into its owner's library.

Storm Reading

Draw four cards, then discard two cards. (Then exile this card. You may cast the creature later from exile.)

Galvanic Giant

Whenever you cast a spell with mana value 5 or greater, tap target creature an opponent controls and put a stun counter on it.

Galvanic Giant // Storm Reading

Wavebreak Hippocamp

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

Blur

Exile target creature you control, then return that card to the battlefield under its owner's control.
Draw a card.

Scour from Existence

Psychosis Crawler

Psychosis Crawler's power and toughness are each equal to the number of cards in your hand.
Whenever you draw a card, each opponent loses 1 life.

Time Reversal

Each player shuffles their hand and graveyard into their library, then draws seven cards. Exile Time Reversal.

Deekah, Fractal Theorist

Magecraft — Whenever you cast or copy an instant or sorcery spell, create a 0/0 green and blue Fractal creature token. Put X +1/+1 counters on it, where X is that spell's mana value.
{3}{U}: Target creature token can't be blocked this turn.

Disallow

Counter target spell, activated ability, or triggered ability. (Mana abilities can't be targeted.)

Reverse the Polarity

Choose one —
• Counter all other spells.
• Switch each creature's power and toughness until end of turn.
• Creatures can't be blocked this turn.

Thassa, Deep-Dwelling

Indestructible
As long as your devotion to blue is less than five, Thassa isn't a creature.
At the beginning of your end step, exile up to one other target creature you control, then return that card to the battlefield under your control.
{3}{U}: Tap another target creature.

Wonder

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

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.

Memory

Aftermath (Cast this spell only from your graveyard. Then exile it.)
Each player shuffles their hand and graveyard into their library, then draws seven cards.

Commit

Put target spell or nonland permanent into its owner's library second from the top.

Commit // Memory

Flow of Knowledge

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

Drown in Dreams

Choose one. If you control a commander as you cast this spell, you may choose both instead.
• Target player draws X cards.
• Target player mills twice X cards.

Clone Legion

For each creature target player controls, create a token that's a copy of that creature.

Sol Ring

Lithoform Engine

{2}, {T}: Copy target activated or triggered ability you control. You may choose new targets for the copy.
{3}, {T}: Copy target instant or sorcery spell you control. You may choose new targets for the copy.
{4}, {T}: Copy target permanent spell you control. (The copy becomes a token.)

The Watcher in the Water

The Watcher in the Water enters tapped with nine stun counters on it. (If a permanent with a stun counter would become untapped, remove one from it instead.)
Whenever you draw a card during an opponent's turn, create a 1/1 blue Tentacle creature token.
Whenever a Tentacle you control dies, untap up to one target Kraken and put a stun counter on up to one target nonland permanent.

Throne of Eldraine

As Throne of Eldraine enters, choose a color.
{T}: Add four mana of the chosen color. Spend this mana only to cast monocolored spells of that color.
{3}, {T}: Draw two cards. Spend only mana of the chosen color to activate this ability.

Pongify

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

Fellwar Stone

{T}: Add one mana of any color that a land an opponent controls could produce.

Curse of the Swine

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

Finale of Revelation

Draw X cards. If X is 10 or more, instead shuffle your graveyard into your library, draw X cards, untap up to five lands, and you have no maximum hand size for the rest of the game.
Exile Finale of Revelation.

Counterspell

Cryptic Command

Choose two —
• Counter target spell.
• Return target permanent to its owner's hand.
• Tap all creatures your opponents control.
• Draw a card.

Horizon Stone

If you would lose unspent mana, that mana becomes colorless instead.

Reenact the Crime

Exile target nonland card in a graveyard that was put there from anywhere this turn. Copy it. You may cast the copy without paying its mana cost.

Frantic Search

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

Inundate

Return all nonblue creatures to their owners' hands.

Lightning Greaves

Equipped creature has haste and shroud. (It can't be the target of spells or abilities.)
Equip {0}

Rewind

Counter target spell. Untap up to four lands.

Charix, the Raging Isle

Spells your opponents cast that target Charix, the Raging Isle cost {2} more to cast.
{3}: Charix gets +X/-X until end of turn, where X is the number of Islands you control.

Mitotic Manipulation

Look at the top seven cards of your library. You may put one of those cards onto the battlefield if it has the same name as a permanent. Put the rest on the bottom of your library in any order.

Imprisoned in the Moon

Enchant creature, land, or planeswalker
Enchanted permanent is a colorless land with "{T}: Add {C}" and loses all other card types and abilities.

Mystic Remora

Cumulative upkeep {1} (At the beginning of your upkeep, put an age counter on this permanent, then sacrifice it unless you pay its upkeep cost for each age counter on it.)
Whenever an opponent casts a noncreature spell, you may draw a card unless that player pays {4}.

Mind Spring

Desertion

Counter target spell. If an artifact or creature spell is countered this way, put that card onto the battlefield under your control instead of into its owner's graveyard.

Sea Gate, Reborn

As Sea Gate, Reborn enters, you may pay 3 life. If you don't, it enters tapped.
{T}: Add {U}.

Sea Gate Restoration

Draw cards equal to the number of cards in your hand plus one. You have no maximum hand size for the rest of the game.

Sea Gate Restoration // Sea Gate, Reborn

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.)

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.

Into the Story

This spell costs {3} less to cast if an opponent has seven or more cards in their graveyard.
Draw four cards.

Chasm Skulker

Whenever you draw a card, put a +1/+1 counter on Chasm Skulker.
When Chasm Skulker dies, create X 1/1 blue Squid creature tokens with islandwalk, where X is the number of +1/+1 counters on Chasm Skulker. (They can't be blocked as long as defending player controls an Island.)

Season of Weaving

Choose up to five {P} worth of modes. You may choose the same mode more than once.
{P} — Draw a card.
{P}{P} — Choose an artifact or creature you control. Create a token that's a copy of it.
{P}{P}{P} — Return each nonland, nontoken permanent to its owner's hand.

Eluge, the Shoreless Sea

Eluge's power and toughness are each equal to the number of Islands you control.
Whenever Eluge enters or attacks, put a flood counter on target land. It's an Island in addition to its other types for as long as it has a flood counter on it.
The first instant or sorcery spell you cast each turn costs {U} (or {1}) less to cast for each land you control with a flood counter on it.

Mystic Reflection

Choose target nonlegendary creature. The next time one or more creatures or planeswalkers enter this turn, they enter as copies of the chosen creature.
Foretell {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.)

Mystic Confluence

Choose three. You may choose the same mode more than once.
• Counter target spell unless its controller pays {3}.
• Return target creature to its owner's hand.
• Draw a card.

Aetherspouts

For each attacking creature, its owner puts it on the top or bottom of their library.

Arcane Signet

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

Rhystic Study

Whenever an opponent casts a spell, you may draw a card unless that player pays {1}.

Nadir Kraken

Whenever you draw a card, you may pay {1}. If you do, put a +1/+1 counter on Nadir Kraken and create a 1/1 blue Tentacle creature token.

Commander's Insight

Target player draws X cards plus an additional card for each time they've cast a commander from the command zone this game.

Wizard Class

(Gain the next level as a sorcery to add its ability.)
You have no maximum hand size.
{2}{U}: Level 2
When this Class becomes level 2, draw two cards.
{4}{U}: Level 3
Whenever you draw a card, put a +1/+1 counter on target creature you control.

Quicksilver Fountain

At the beginning of each player's upkeep, that player puts a flood counter on target non-Island land they control of their choice. That land is an Island for as long as it has a flood counter on it.
At the beginning of each end step, if all lands on the battlefield are Islands, remove all flood counters from them.

Kira, Great Glass-Spinner

Flying
Creatures you control have "Whenever this creature becomes the target of a spell or ability for the first time each turn, counter that spell or ability."