High Tide

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

Skittering Crustacean

{6}{U}: Monstrosity 4. (If this creature isn't monstrous, put four +1/+1 counters on it and it becomes monstrous.)
As long as this creature is monstrous, it has hexproof. (It can't be the target of spells or abilities your opponents control.)

Misleading Signpost

Flash
When this artifact enters during the declare attackers step, you may reselect which player or permanent target attacking creature is attacking. (It can't attack its controller or their permanents.)
{T}: Add {U}.

Saprazzan Cove

This land enters tapped.
{T}: Put a storage counter on this land.
{T}, Remove any number of storage counters from this land: Add {U} for each storage counter removed this way.

Wishcoin Crab

Mirelurk Queen

Vigilance
When this creature enters, target player gets two rad counters.
Whenever one or more nonland cards are milled, draw a card, then put a +1/+1 counter on this creature. This ability triggers only once each turn.

Charix, the Raging Isle

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

Coastal Bulwark

Defender
This creature gets +2/+0 as long as you control an Island.
{2}, {T}: Surveil 1. (Look at the top card of your library. You may put that card into your graveyard.)

Horseshoe Crab

Hightide Hermit

Defender
When this creature enters, you get {E}{E}{E}{E} (four energy counters).
Pay {E}{E}: This creature can attack this turn as though it didn't have defender.

Thassa's Bounty

Draw three cards. Target player mills three cards.

Dazzling Denial

Counter target spell unless its controller pays {2}. If you control a Bird, counter that spell unless its controller pays {4} instead.

Fleet Swallower

Whenever this creature attacks, target player mills half their library, rounded up.

Homarid Shaman

Thassa's Emissary

Bestow {5}{U} (If you cast this card for its bestow cost, it's an Aura spell with enchant creature. It becomes a creature again if it's not attached.)
Whenever this creature or enchanted creature deals combat damage to a player, draw a card.
Enchanted creature gets +3/+3.

Snow-Covered Island

Drownyard Behemoth

Flash (You may cast this spell any time you could cast an instant.)
Emerge {7}{U} (You may cast this spell by sacrificing a creature and paying the emerge cost reduced by that creature's mana value.)
This creature has hexproof as long as it entered this turn.

Trade the Helm

Exchange control of target artifact or creature you control and target artifact or creature an opponent controls.
Cycling {2} ({2}, Discard this card: Draw a card.)

Crab Umbra

Enchant creature
{2}{U}: Untap enchanted creature.
Umbra armor (If enchanted creature would be destroyed, instead remove all damage from it and destroy this Aura.)

Fortress Crab

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.

Glimpse of Freedom

Draw a card.
Escape—{2}{U}, Exile five other cards from your graveyard. (You may cast this card from your graveyard for its escape cost.)

The Water Crystal

Blue spells you cast cost {1} less to cast.
If an opponent would mill one or more cards, they mill that many cards plus four instead.
{4}{U}{U}, {T}: Each opponent mills cards equal to the number of cards in your hand.

Depths of Desire

Return target creature to its owner's hand. Create a Treasure token. (It's an artifact with "{T}, Sacrifice this token: Add one mana of any color.")

Hullbreaker Horror

Flash
This spell can't be countered.
Whenever you cast a spell, choose up to one —
• Return target spell you don't control to its owner's hand.
• Return target nonland permanent to its owner's hand.

Iceberg Cancrix

Whenever another snow permanent you control enters, you may have target player mill two cards.

Wasteland

{T}: Add {C}.
{T}, Sacrifice this land: Destroy target nonbasic land.

Mirrorshell Crab

Ward {3} (Whenever this creature becomes the target of a spell or ability an opponent controls, counter it unless that player pays {3}.)
Channel — {2}{U}, Discard this card: Counter target spell or ability unless its controller pays {3}.

Thassa, God of the Sea

Indestructible
As long as your devotion to blue is less than five, Thassa isn't a creature. (Each {U} in the mana costs of permanents you control counts toward your devotion to blue.)
At the beginning of your upkeep, scry 1.
{1}{U}: Target creature you control can't be blocked this turn.

Armored Cancrix

Ruin Crab

Landfall — Whenever a land you control enters, each opponent mills three cards. (To mill a card, a player puts the top card of their library into their graveyard.)

Into the Flood Maw

Gift a tapped Fish (You may promise an opponent a gift as you cast this spell. If you do, they create a tapped 1/1 blue Fish creature token before its other effects.)
Return target creature an opponent controls to its owner's hand. If the gift was promised, instead return target nonland permanent an opponent controls to its owner's hand.

Homarid Explorer

When this creature enters, target player mills four cards.

Gilded Scuttler

This creature can't be blocked.
When this creature enters, tap target creature an opponent controls and put a stun counter on it. (If a permanent with a stun counter would become untapped, remove one from it instead.)

Specimen Collector

When this creature enters, create a 1/1 green Squirrel creature token and a 0/3 blue Crab creature token.
When this creature dies, create a token that's a copy of target token you control.

Crystacean

Flash (You may cast this spell any time you could cast an instant.)

Aether Barrier

Whenever a player casts a creature spell, that player sacrifices a permanent of their choice unless they pay {1}.

Reef Pirates

Whenever this creature deals damage to an opponent, that player mills a card.

Skitter Eel

{2}{U}: Adapt 2. (If this creature has no +1/+1 counters on it, put two +1/+1 counters on it.)

Chromeshell Crab

Morph {4}{U} (You may cast this card face down as a 2/2 creature for {3}. Turn it face up any time for its morph cost.)
When this creature is turned face up, you may exchange control of target creature you control and target creature an opponent controls.

Vexing Scuttler

Emerge {6}{U} (You may cast this spell by sacrificing a creature and paying the emerge cost reduced by that creature's mana value.)
When you cast this spell, you may return target instant or sorcery card from your graveyard to your hand.

Sea Scryer

Myriad Landscape

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

Spell Pierce

Counter target noncreature spell unless its controller pays {2}.

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.

Canyon Crab

{1}{U}: This creature gets +2/-2 until end of turn.
At the beginning of your end step, if you haven't cast a spell from your hand this turn, draw a card, then discard a card.

Wormfang Crab

This creature can't be blocked.
When this creature enters, an opponent chooses a permanent you control other than this creature and exiles it.
When this creature leaves the battlefield, return the exiled card to the battlefield under its owner's control.

Brainstorm

Draw three cards, then put two cards from your hand on top of your library in any order.

Hedron Crab

Landfall — Whenever a land you control enters, target player mills three cards. (They put the top three cards of their library into their graveyard.)

Thought Vessel

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

Purple-Crystal Crab

Oraxid

Delightful Discovery

This spell costs {1} less to cast for each spell your opponents have cast this turn.
Scry 2, then draw two cards. (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.)

Treasure Cove

(Transforms from Treasure Map.)
{T}: Add {C}.
{T}, Sacrifice a Treasure: Draw a card.

Treasure Map

{1}, {T}: Scry 1. Put a landmark counter on this artifact. Then if there are three or more landmark counters on it, remove those counters, transform this artifact, and create three Treasure tokens. (They're artifacts with "{T}, Sacrifice this token: Add one mana of any color.")

Treasure Map // Treasure Cove

Pirate's Prize

Draw two cards. Create a Treasure token. (It's an artifact with "{T}, Sacrifice this token: Add one mana of any color.")

Compulsive Research

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

Riptide Pilferer

Whenever this creature deals combat damage to a player, that player discards a card.
Morph {U} (You may cast this card face down as a 2/2 creature for {3}. Turn it face up any time for its morph cost.)

Shorecomber Crab

Shipwreck Looter

Raid — When this creature enters, if you attacked this turn, you may draw a card. If you do, discard a card.

Coral Colony

Defender
{1}{U}, {T}: Target player mills X cards, where X is the number of creatures you control with defender. (To mill a card, a player puts the top card of their library into their graveyard.)

Coastal Piracy

Whenever a creature you control deals combat damage to an opponent, you may draw a card.

Giant Crab

{U}: This creature gains shroud until end of turn. (It can't be the target of spells or abilities.)

Forsaken Thresher

At the beginning of your first main phase, add one mana of any color.

Foreboding Statue

{T}: Add one mana of any color. Put an omen counter on this creature.
At the beginning of your end step, if there are three or more omen counters on this creature, untap it, then transform it.

Foreboding Statue // Forsaken Thresher

Ancient Crab

Scuttling Doom Engine

This creature can't be blocked by creatures with power 2 or less.
When this creature dies, it deals 6 damage to target opponent or planeswalker.

Eddymurk Crab

Flash
This spell costs {1} less to cast for each instant and sorcery card in your graveyard.
This creature enters tapped if it's not your turn.
When this creature enters, tap up to two target creatures.