Adaptive Automaton

As this creature enters, choose a creature type.
This creature is the chosen type in addition to its other types.
Other creatures you control of the chosen type get +1/+1.

High Tide

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

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.)

Reflections of Littjara

As this enchantment enters, choose a creature type.
Whenever you cast a spell of the chosen type, copy that spell. (A copy of a permanent spell becomes a token.)

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.

Shell Shield

Kicker {1} (You may pay an additional {1} as you cast this spell.)
Target creature you control gets +0/+3 until end of turn. If this spell was kicked, that creature also gains hexproof until end of turn. (It can't be the target of spells or abilities your opponents control.)

Sapphire Medallion

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

Fortress Crab

Levitation

Patchwork Banner

As this artifact enters, choose a creature type.
Creatures you control of the chosen type get +1/+1.
{T}: Add one mana of any color.

Horseshoe Crab

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.

Counterspell

Engulf the Shore

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

Sleep

Tap all creatures target player controls. Those creatures don't untap during that player's next untap step.

Wishcoin Crab

Banner of Kinship

As this artifact enters, choose a creature type. This artifact enters with a fellowship counter on it for each creature you control of the chosen type.
Creatures you control of the chosen type get +1/+1 for each fellowship counter on this artifact.

Kasmina, Enigmatic Mentor

Spells your opponents cast that target a creature or planeswalker you control cost {2} more to cast.
−2: Create a 2/2 blue Wizard creature token. Draw a card, then discard a card.

Heraldic Banner

As this artifact enters, choose a color.
Creatures you control of the chosen color get +1/+0.
{T}: Add one mana of the chosen color.

Sol Ring

Kindred Discovery

As this enchantment enters, choose a creature type.
Whenever a creature you control of the chosen type enters or attacks, draw a card.

Arcane Signet

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

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.

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}.

Crystacean

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

Hard Evidence

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

Burnished Hart

{3}, Sacrifice this creature: Search your library for up to two basic land cards, put them onto the battlefield tapped, then shuffle.

Scourge of Fleets

When this creature 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.

Enter the Enigma

Target creature can't be blocked this turn.
Draw a card.

Walking Atlas

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

Slip Through Space

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

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.

Scrabbling Skullcrab

Eerie — Whenever an enchantment you control enters and whenever you fully unlock a Room, target player mills two cards. (They put the top two cards of their library into their graveyard.)

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.)

Flow of Ideas

Pongify

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

Raise the Palisade

Choose a creature type. Return all creatures that aren't of the chosen type to their owners' hands.

Solemn Simulacrum

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

Terramorphic Expanse

{T}, Sacrifice this land: Search your library for a basic land card, put it onto the battlefield tapped, then shuffle.

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.

Twisted Image

Switch target creature's power and toughness until end of turn.
Draw a card.

Rewind

Counter target spell. Untap up to four lands.

Shore Up

Target creature you control gets +1/+1 and gains hexproof until end of turn. Untap it. (It can't be the target of spells or abilities your opponents control.)

Mu Yanling

+2: Target creature can't be blocked this turn.
−3: Draw two cards.
−10: Tap all creatures your opponents control. You take an extra turn after this one.

Reliquary Tower

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

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.

Wonder

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

Cavern of Souls

As this land enters, choose a creature type.
{T}: Add {C}.
{T}: Add one mana of any color. Spend this mana only to cast a creature spell of the chosen type, and that spell can't be countered.

Temple of the False God

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

Purple-Crystal Crab

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.

Evolving Wilds

Ancient Crab

Stormtide Leviathan

Islandwalk (This creature can't be blocked as long as defending player controls an Island.)
All lands are Islands in addition to their other types.
Creatures without flying or islandwalk can't attack.

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.

Blackblade Reforged

Equipped creature gets +1/+1 for each land you control.
Equip legendary creature {3}
Equip {7}

Shorecomber Crab

Propaganda

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

Terrain Generator

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

Island

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.)

Flow of Knowledge

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

Dreadlight Monstrosity

Ward {2} (Whenever this creature becomes the target of a spell or ability an opponent controls, counter it unless that player pays {2}.)
{3}{U}{U}: This creature can't be blocked this turn. Activate only if you own a card in exile.

Rhystic Study

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

Thought Vessel

Cathar's Shield

Equipped creature gets +0/+3 and has vigilance.
Equip {3} ({3}: Attach to target creature you control. Equip only as a sorcery.)

Merfolk Thaumaturgist

{T}: Switch target creature's power and toughness until end of turn.

Aqueous Form

Enchant creature
Enchanted creature can't be blocked.
Whenever enchanted creature attacks, scry 1. (Look at the top card of your library. You may put that card on the bottom.)

Path of Ancestry

This land enters tapped.
{T}: Add one mana of any color in your commander's color identity. When that mana is spent to cast a creature spell that shares a creature type with your commander, scry 1. (Look at the top card of your library. You may put that card on the bottom.)

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.

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.)