Rampant Growth

Search your library for a basic land card, put that card onto the battlefield tapped, then shuffle.

Krosan Grip

Split second (As long as this spell is on the stack, players can't cast spells or activate abilities that aren't mana abilities.)
Destroy target artifact or enchantment.

Pongify

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

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.

High Alert

Each creature you control assigns combat damage equal to its toughness rather than its power.
Creatures you control can attack as though they didn't have defender.
{2}{W}{U}: Untap target creature.

Distant Melody

Choose a creature type. Draw a card for each permanent you control of that type.

Purple-Crystal Crab

Shambleshark

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

Terramorphic Expanse

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

Return to Nature

Choose one —
• Destroy target artifact.
• Destroy target enchantment.
• Exile target card from a graveyard.

Generous Gift

Destroy target permanent. Its controller creates a 3/3 green Elephant creature token.

Riptide Crab

Vigilance
When this creature dies, draw a card.

Frantic Search

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

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.

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.

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.

Sharktocrab

{2}{G}{U}: Adapt 1. (If this creature has no +1/+1 counters on it, put a +1/+1 counter on it.)
Whenever one or more +1/+1 counters are put on this creature, tap target creature an opponent controls. That creature doesn't untap during its controller's next untap step.

Guardian Project

Whenever a nontoken creature you control enters, if it doesn't have the same name as another creature you control or a creature card in your graveyard, draw a card.

Tribal Unity

Creatures of the creature type of your choice get +X/+X until end of turn.

Beast Within

Destroy target permanent. Its controller creates a 3/3 green Beast creature token.

Dawn

Aftermath (Cast this spell only from your graveyard. Then exile it.)
Return all creature cards with power 2 or less from your graveyard to your hand.

Dusk

Destroy all creatures with power 3 or greater.

Dusk // Dawn

Exotic Orchard

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

Ancient Crab

Mirror Entity

Changeling (This card is every creature type.)
{X}: Until end of turn, creatures you control have base power and toughness X/X and gain all creature types.

Arcane Signet

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

Scuttlegator

Defender
{6}{G/U}{G/U}: Adapt 3. (If this creature has no +1/+1 counters on it, put three +1/+1 counters on it.)
As long as this creature has a +1/+1 counter on it, it can attack as though it didn't have defender.

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.

Evolving Wilds

Path to Exile

Exile target creature. Its controller may search their library for a basic land card, put that card onto the battlefield tapped, then shuffle.

Command Tower

Unbreakable Formation

Creatures you control gain indestructible until end of turn.
Addendum — If you cast this spell during your main phase, put a +1/+1 counter on each of those creatures and they gain vigilance until end of turn.

Seaside Citadel

This land enters tapped.
{T}: Add {G}, {W}, or {U}.

Stroke of Midnight

Destroy target nonland permanent. Its controller creates a 1/1 white Human creature token.

Scuttling Sentinel

Flash
Vigilance
When this creature enters, put a +1/+1 counter on another target creature you control. Until end of turn, that creature becomes a blue Crab in addition to its other types and gains hexproof. (It can't be the target of spells or abilities your opponents control.)

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.

Sol Ring

Simic Keyrune

{T}: Add {G} or {U}.
{G}{U}: This artifact becomes a 2/3 green and blue Crab artifact creature with hexproof until end of turn. (It can't be the target of spells or abilities your opponents control.)

Crystacean

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

Explore

You may play an additional land this turn.
Draw a card.

Rally the Ranks

As this enchantment enters, choose a creature type.
Creatures you control of the chosen type get +1/+1.

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.

And They Shall Know No Fear

Choose a creature type. Creatures you control of the chosen type get +1/+0 and gain indestructible until end of turn.

Bloodline Pretender

Changeling (This card is every creature type.)
As this creature enters, choose a creature type.
Whenever another creature you control of the chosen type enters, put a +1/+1 counter on this creature.

Wayfarer's Bauble

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

Ragnar

{G}{W}{U}, {T}: Regenerate target creature.

Unsettled Mariner

Changeling (This card is every creature type.)
Whenever you or a permanent you control becomes the target of a spell or ability an opponent controls, counter that spell or ability unless its controller pays {1}.

Farseek

Search your library for a Plains, Island, Swamp, or Mountain card, put it onto the battlefield tapped, then shuffle.

Ponder

Look at the top three cards of your library, then put them back in any order. You may shuffle.
Draw a card.

Alpha Status

Enchant creature
Enchanted creature gets +2/+2 for each other creature on the battlefield that shares a creature type with it.

Chromatic Lantern

Lands you control have "{T}: Add one mana of any color."
{T}: Add one mana of any color.

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.")

King Crab

{1}{U}, {T}: Put target green creature on top of its owner's library.

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.

Preordain

Scry 2, then draw a card. (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.)

Radiant Destiny

Ascend (If you control ten or more permanents, you get the city's blessing for the rest of the game.)
As this enchantment enters, choose a creature type.
Creatures you control of the chosen type get +1/+1. As long as you have the city's blessing, they also have vigilance.

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.

Frogify

Enchant creature
Enchanted creature loses all abilities and is a blue Frog creature with base power and toughness 1/1. (It loses all other card types and creature types.)

Kefnet's Monument

Blue creature spells you cast cost {1} less to cast.
Whenever you cast a creature spell, target creature an opponent controls doesn't untap during its controller's next untap step.

Swords to Plowshares

Exile target creature. Its controller gains life equal to its power.

Metallic Mimic

As this creature enters, choose a creature type.
This creature is the chosen type in addition to its other types.
Each other creature you control of the chosen type enters with an additional +1/+1 counter on it.

Misdirection

You may exile a blue card from your hand rather than pay this spell's mana cost.
Change the target of target spell with a single target.

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.

Access Tunnel

{T}: Add {C}.
{3}, {T}: Target creature with power 3 or less can't be blocked this turn.

Giant Crab

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

Herald's Horn

As this artifact enters, choose a creature type.
Creature spells you cast of the chosen type cost {1} less to cast.
At the beginning of your upkeep, look at the top card of your library. If it's a creature card of the chosen type, you may reveal it and put it into your hand.

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.

Wash Out

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

High Tide

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

Vanquisher's Banner

As this artifact enters, choose a creature type.
Creatures you control of the chosen type get +1/+1.
Whenever you cast a creature spell of the chosen type, draw a card.

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.

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.

Realmwalker

Changeling (This card is every creature type.)
As this creature enters, choose a creature type.
You may look at the top card of your library any time.
You may cast creature spells of the chosen type from the top of your library.

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.)