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}.

Ice Floe

You may choose not to untap this land during your untap step.
{T}: Tap target creature without flying that's attacking you. It doesn't untap during its controller's untap step for as long as this land remains tapped.

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.)

Counterspell

Blind Seer

{1}{U}: Target spell or permanent becomes the color of your choice until end of turn.

Metathran Transport

Flying
This creature can't be blocked by blue creatures.
{U}: Target creature becomes blue until end of turn.

Mind Bend

Change the text of target permanent by replacing all instances of one color word with another or one basic land type with another. (For example, you may change "nonblack creature" to "nongreen creature" or "forestwalk" to "islandwalk." This effect lasts indefinitely.)

Insight

Whenever an opponent casts a green spell, you draw a card.

Rhystic Study

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

Llawan, Cephalid Empress

When Llawan enters, return all blue creatures your opponents control to their owners' hands.
Your opponents can't cast blue creature spells.

Temporal Adept

{U}{U}{U}, {T}: Return target permanent to its owner's hand.

Vesuvan Doppelganger

You may have this creature enter as a copy of any creature on the battlefield, except it doesn't copy that creature's color and it has "At the beginning of your upkeep, you may have this creature become a copy of target creature, except it doesn't copy that creature's color and it has this ability."

Blatant Thievery

For each opponent, gain control of target permanent that player controls.

Faerie Conclave

This land enters tapped.
{T}: Add {U}.
{1}{U}: This land becomes a 2/1 blue Faerie creature with flying until end of turn. It's still a land.

Remote Isle

This land enters tapped.
{T}: Add {U}.
Cycling {2} ({2}, Discard this card: Draw a card.)

Capsize

Buyback {3} (You may pay an additional {3} as you cast this spell. If you do, put this card into your hand as it resolves.)
Return target permanent to its owner's hand.

Snap

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

Lonely Sandbar

This land enters tapped.
{T}: Add {U}.
Cycling {U} ({U}, Discard this card: Draw a card.)

Distorting Wake

Return X target nonland permanents to their owners' hands.

Fylamarid

Whim of Volrath

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.)
Change the text of target permanent by replacing all instances of one color word with another or one basic land type with another until end of turn. (For example, you may change "nonred creature" to "nongreen creature" or "plainswalk" to "swampwalk.")

Syncopate

Counter target spell unless its controller pays {X}. If that spell is countered this way, exile it instead of putting it into its owner's graveyard.

Star Compass

This artifact enters tapped.
{T}: Add one mana of any color that a basic land you control could produce.

Flood

{U}{U}: Tap target creature without flying.

Dismiss

Fog Bank

Defender (This creature can't attack.)
Flying
Prevent all combat damage that would be dealt to and dealt by this creature.

Shifting Sky

As this enchantment enters, choose a color.
All nonland permanents are the chosen color.

Mana Leak

Counter target spell unless its controller pays {3}.

Empress Galina

{U}{U}, {T}: Gain control of target legendary permanent. (This effect lasts indefinitely.)

Opposition

Tap an untapped creature you control: Tap target artifact, creature, or land.

High Tide

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

Fellwar Stone

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

Wash Out

Return all permanents of the color of your choice to their owners' hands.

Equilibrium

Whenever you cast a creature spell, you may pay {1}. If you do, return target creature to its owner's hand.

Temple of the False God

{T}: Add {C}{C}. Activate only if you control five or more lands.

Sway of Illusion

Any number of target creatures become the color of your choice until end of turn.
Draw a card.

Ensnaring Bridge

Creatures with power greater than the number of cards in your hand can't attack.

Floodgate

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

Chill

Sea Kings' Blessing

One or more target creatures become blue until end of turn.

Crystal Spray

Change the text of target spell or permanent by replacing all instances of one color word with another or one basic land type with another until end of turn.
Draw a card.

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.

Sapphire Medallion

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

Aboshan, Cephalid Emperor

Tap an untapped Octopus you control: Tap target permanent.
{U}{U}{U}: Tap all creatures without flying.

Erratic Portal

{1}, {T}: Return target creature to its owner's hand unless its controller pays {1}.

Sky Diamond

This artifact enters tapped.
{T}: Add {U}.

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.

Propaganda

Creatures can't attack you unless their controller pays {2} for each creature they control that's attacking you.

Island

Control Magic

Enchant creature
You control enchanted creature.

Dream Tides

Creatures don't untap during their controllers' untap steps.
At the beginning of each player's upkeep, that player may choose any number of tapped nongreen creatures they control and pay {2} for each creature chosen this way. If the player does, untap those creatures.

Coral Atoll

This land enters tapped.
When this land enters, sacrifice it unless you return an untapped Island you control to its owner's hand.
{T}: Add {C}{U}.

Vodalian Mage

{U}, {T}: Counter target spell unless its controller pays {1}.

Callous Oppressor

You may choose not to untap this creature during your untap step.
As this creature enters, an opponent chooses a creature type.
{T}: Gain control of target creature that isn't of the chosen type for as long as this creature remains tapped.

Sleight of Mind

Change the text of target spell or permanent by replacing all instances of one color word with another. (For example, you may change "target black spell" to "target blue spell." This effect lasts indefinitely.)

Back to Basics

Nonbasic lands don't untap during their controllers' untap steps.

Reins of Power

Untap all creatures you control and all creatures target opponent controls. You and that opponent each gain control of all creatures the other controls until end of turn. Those creatures gain haste until end of turn.

Standstill

When a player casts a spell, sacrifice this enchantment. If you do, each of that player's opponents draws three cards.

High Seas

Red creature spells and green creature spells cost {1} more to cast.

Alter Reality

Change the text of target spell or permanent by replacing all instances of one color word with another. (This effect lasts indefinitely.)
Flashback {1}{U} (You may cast this card from your graveyard for its flashback cost. Then exile it.)

Spiny Starfish

{U}: Regenerate this creature.
At the beginning of each end step, if this creature regenerated this turn, create a 0/1 blue Starfish creature token for each time it regenerated this turn.

Meekstone

Creatures with power 3 or greater don't untap during their controllers' untap steps.

Hibernation

Return all green permanents to their owners' hands.

Shimmer

As this enchantment enters, choose a land type.
Each land of the chosen type has phasing. (It phases in or out before its controller untaps during each of their untap steps. While it's phased out, it's treated as though it doesn't exist.)

Sol Ring

Jayemdae Tome

Dissipate

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