Aethersnatch

Gain control of target spell. You may choose new targets for it. (If that spell becomes a permanent, it enters under your control.)

Breaking Wave

You may cast this spell as though it had flash if you pay {2} more to cast it. (You may cast it any time you could cast an instant.)
Simultaneously untap all tapped creatures and tap all untapped creatures.

Horseshoe Crab

Tidal Surge

Tap up to three target creatures without flying.

Iceberg Cancrix

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

Aetherspouts

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

Island

Tidal Control

Cumulative upkeep {2} (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.)
Pay 2 life or {2}: Counter target red or green spell. Any player may activate this ability.

Aether Tunnel

Enchant creature
Enchanted creature gets +1/+0 and can't be blocked.

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.)

Aether Tide

As an additional cost to cast this spell, discard X creature cards.
Return X target creatures to their owners' hands.

Unsummon

Return target creature to its owner's hand.

Aether Spellbomb

{U}, Sacrifice this artifact: Return target creature to its owner's hand.
{1}, Sacrifice this artifact: Draw a card.

Symbol of Unsummoning

Return target creature to its owner's hand.
Draw a card.

Tidal Bore

You may return an Island you control to its owner's hand rather than pay this spell's mana cost.
You may tap or untap target creature.

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.)

Scrabbling Claws

{T}: Target player exiles a card from their graveyard.
{1}, Sacrifice this artifact: Exile target card from a graveyard. Draw a card.

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.

Armored Cancrix

Purple-Crystal Crab

Salvage Scuttler

Whenever this creature attacks, return an artifact you control to its owner's hand.

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.)

Man-o'-War

When this creature enters, return target creature to its owner's hand.

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.

Avizoa

Flying
{0}: This creature gets +2/+2 until end of turn. You skip your next untap step. Activate only once each turn.

Clinging Anemones

Defender
Evolve (Whenever a creature you control enters, if that creature has greater power or toughness than this creature, put a +1/+1 counter on this creature.)

Crystacean

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

Power Sink

Counter target spell unless its controller pays {X}. If that player doesn't, they tap all lands with mana abilities they control and lose all unspent mana.

Ancient Crab

Chronozoa

Flying
Vanishing 3 (This creature enters with three time counters on it. At the beginning of your upkeep, remove a time counter from it. When the last is removed, sacrifice it.)
When this creature dies, if it had no time counters on it, create two tokens that are copies of it.

Fortress Crab

Aetherize

Return all attacking creatures to their owner's hand.

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 to a creature.)
Whenever this creature or enchanted creature deals combat damage to a player, draw a card.
Enchanted creature gets +3/+3.

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.

Aether Gust

Choose target spell or permanent that's red or green. Its owner puts it on their choice of the top or bottom of their library.

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.

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.

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.

Wishcoin Crab

Sigiled Starfish

{T}: Scry 1. (Look at the top card of your library. You may put that card on the bottom.)

Command of Unsummoning

Cast this spell only during the declare attackers step and only if you've been attacked this step.
Return one or two target attacking creatures to their owner's hand.

Aether Tradewinds

Return target permanent you control and target permanent you don't control to their owners' hands.

Glimmerbell

Scuttletide

{1}, Discard a card: Create a 0/3 blue Crab creature token.
Delirium — Crabs you control get +1/+1 as long as there are four or more card types among cards in your graveyard.

Hedron Crab

Landfall — Whenever a land you control enters, target player mills three cards.

Gomazoa

Defender, flying
{T}: Put this creature and each creature it's blocking on top of their owners' libraries, then those players shuffle.

Anchor to the Aether

Put target creature on top of its owner's library. Scry 1. (Look at the top card of your library. You may put that card on the bottom.)

Glowing Anemone

When this creature enters, you may return target land to its owner's hand.

Tidal Wave

Create a 5/5 blue Wall creature token with defender. Sacrifice it at the beginning of the next end step.

Dormant Gomazoa

Flying
This creature enters tapped.
This creature doesn't untap during your untap step.
Whenever you become the target of a spell, you may untap this creature.

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.

Jwari Scuttler

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.

Esperzoa

Flying
At the beginning of your upkeep, return an artifact you control to its owner's hand.

Aether Meltdown

Flash (You may cast this spell any time you could cast an instant.)
Enchant creature or Vehicle
When this Aura enters, you get {E}{E} (two energy counters).
Enchanted creature gets -4/-0.

Guard Gomazoa

Defender, flying
Prevent all combat damage that would be dealt to Guard Gomazoa.

Sinking Feeling

Enchant creature
Enchanted creature doesn't untap during its controller's untap step.
Enchanted creature has "{1}, Put a -1/-1 counter on this creature: Untap this creature."