Hammerhead Shark

This creature can't attack unless defending player controls an Island.

Mana Skimmer

Flying
Whenever this creature deals damage to a player, tap target land that player controls. That land doesn't untap during its controller's next untap step.

Ambassador Laquatus

War-Wing Siren

Flying
Heroic — Whenever you cast a spell that targets this creature, put a +1/+1 counter on this creature.

Cache Raiders

At the beginning of your upkeep, return a permanent you control to its owner's hand.

Siren Stormtamer

Flying
{U}, Sacrifice this creature: Counter target spell or ability that targets you or a creature you control.

Admiral Beckett Brass

Other Pirates you control get +1/+1.
At the beginning of your end step, gain control of target nonland permanent controlled by a player who was dealt combat damage by three or more Pirates this turn.

Shoal Kraken

Constellation — Whenever an enchantment you control enters, you may draw a card. If you do, discard a card.

Shipwreck Looter

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

Ghost Ship

Flying
{U}{U}{U}: Regenerate this creature.

Siren Lookout

Flying
When this creature enters, it explores. (Reveal the top card of your library. Put that card into your hand if it's a land. Otherwise, put a +1/+1 counter on this creature, then put the card back or put it into your graveyard.)

Mountain

Dreamcaller Siren

Flash
Flying
This creature can block only creatures with flying.
When this creature enters, if you control another Pirate, tap up to two target nonland permanents.

Golden Urn

At the beginning of your upkeep, you may put a charge counter on this artifact.
{T}, Sacrifice this artifact: You gain life equal to the number of charge counters on this artifact.

Coralhelm Commander

Level up {1} ({1}: Put a level counter on this. Level up only as a sorcery.)
LEVEL 2-3
3/3
Flying
LEVEL 4+
4/4
Flying
Other Merfolk creatures you control get +1/+1.

Volcanic Island

Coral Trickster

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.)
When this creature is turned face up, you may tap or untap target permanent.

Cloud Pirates

Flying
This creature can block only creatures with flying.

The Omenkeel

Whenever a Vehicle you control deals combat damage to a player, that player exiles that many cards from the top of their library. You may play lands from among those cards for as long as they remain exiled.
Crew 1

Cosima, God of the Voyage

At the beginning of your upkeep, you may exile Cosima. If you do, it gains "Whenever a land you control enters, if Cosima is exiled, you may put a voyage counter on it. If you don't, return Cosima to the battlefield with X +1/+1 counters on it and draw X cards, where X is the number of voyage counters on it."

Cosima, God of the Voyage // The Omenkeel

Wanderbrine Rootcutters

This creature can't be blocked by green creatures.

Mox Diamond

If this artifact would enter, you may discard a land card instead. If you do, put this artifact onto the battlefield. If you don't, put it into its owner's graveyard.
{T}: Add one mana of any color.

Reef Pirates

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

Zareth San, the Trickster

Flash
{2}{U}{B}, Return an unblocked attacking Rogue you control to its owner's hand: Put this card from your hand onto the battlefield tapped and attacking.
Whenever Zareth San deals combat damage to a player, you may put target permanent card from that player's graveyard onto the battlefield under your control.

Dargo, the Shipwrecker

As an additional cost to cast this spell, you may sacrifice any number of artifacts and/or creatures. This spell costs {2} less to cast for each permanent sacrificed this way and {2} less to cast for each other artifact or creature you've sacrificed this turn.
Trample
Partner (You can have two commanders if both have partner.)

Icebreaker Kraken

Affinity for snow lands (This spell costs {1} less to cast for each snow land you control.)
When this creature enters, artifacts and creatures target opponent controls don't untap during that player's next untap step.
Return three snow lands you control to their owner's hand: Return this creature to its owner's hand.

Catacomb Slug

Island

Araumi of the Dead Tide

{T}, Exile cards from your graveyard equal to the number of opponents you have: Target creature card in your graveyard gains encore until end of turn. The encore cost is equal to its mana cost. (Exile the creature card and pay its mana cost: For each opponent, create a token copy that attacks that opponent this turn if able. They gain haste. Sacrifice them at the beginning of the next end step. Activate only as a sorcery.)

Kraken's Eye

Whenever a player casts a blue spell, you may gain 1 life.

Gravelgill Axeshark

Persist (When this creature dies, if it had no -1/-1 counters on it, return it to the battlefield under its owner's control with a -1/-1 counter on it.)

Brineborn Cutthroat

Flash (You may cast this spell any time you could cast an instant.)
Whenever you cast a spell during an opponent's turn, put a +1/+1 counter on this creature.

Augur of Bolas

When this creature enters, look at the top three cards of your library. You may reveal an instant or sorcery card from among them and put it into your hand. Put the rest on the bottom of your library in any order.

Immersturm Skullcairn

This land enters tapped.
{T}: Add {B}.
{1}{B}{R}{R}, {T}, Sacrifice this land: It deals 3 damage to target player. That player discards a card. Activate only as a sorcery.

Sygg, River Cutthroat

At the beginning of each end step, if an opponent lost 3 or more life this turn, you may draw a card. (Damage causes loss of life.)

Nadir Kraken

Whenever you draw a card, you may pay {1}. If you do, put a +1/+1 counter on this creature and create a 1/1 blue Tentacle creature token.

Fell Flagship

Pirates you control get +1/+0.
Whenever this Vehicle deals combat damage to a player, that player discards a card.
Crew 3 (Tap any number of creatures you control with total power 3 or more: This Vehicle becomes an artifact creature until end of turn.)

Archmage Emeritus

Magecraft — Whenever you cast or copy an instant or sorcery spell, draw a card.

Swamp

Drowner Initiate

Whenever a player casts a blue spell, you may pay {1}. If you do, target player mills two cards.

Ephemeron

Flying
Discard a card: Return this creature to its owner's hand.

Giant Slug

{5}: At the beginning of your next upkeep, choose a basic land type. This creature gains landwalk of the chosen type until the end of that turn. (It can't be blocked as long as defending player controls a land of that type.)

Brinelin, the Moon Kraken

When Brinelin enters and whenever you cast a spell with mana value 6 or greater, you may return target nonland permanent to its owner's hand.
Partner (You can have two commanders if both have partner.)

Lochmere Serpent

Flash
{U}, Sacrifice an Island: This creature can't be blocked this turn.
{B}, Sacrifice a Swamp: You gain 1 life and draw a card.
{U}{B}: Exile five target cards from an opponent's graveyard. Return this card from your graveyard to your hand. Activate only as a sorcery.

Emergence Zone

{T}: Add {C}.
{1}, {T}, Sacrifice this land: You may cast spells this turn as though they had flash.

Siren of the Silent Song

Flying
Inspired — Whenever this creature becomes untapped, each opponent discards a card, then each opponent mills a card.

Moonring Island

({T}: Add {U}.)
This land enters tapped.
{U}, {T}: Look at the top card of target player's library. Activate only if you control two or more blue permanents.

Skysovereign, Consul Flagship

Flying
Whenever Skysovereign enters or attacks, it deals 3 damage to target creature or planeswalker an opponent controls.
Crew 3 (Tap any number of creatures you control with total power 3 or more: This Vehicle becomes an artifact creature until end of turn.)

Kari Zev, Skyship Raider

First strike, menace
Whenever Kari Zev attacks, create Ragavan, a legendary 2/1 red Monkey creature token. Ragavan enters tapped and attacking. Exile that token at end of combat.

Deeptread Merrow

{U}: This creature gains islandwalk until end of turn. (It can't be blocked as long as defending player controls an Island.)

Glimmervoid

At the beginning of the end step, if you control no artifacts, sacrifice this land.
{T}: Add one mana of any color.

Hypnotic Siren

Bestow {5}{U}{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.)
Flying
You control enchanted creature.
Enchanted creature gets +1/+1 and has flying.

Shipbreaker Kraken

{6}{U}{U}: Monstrosity 4. (If this creature isn't monstrous, put four +1/+1 counters on it and it becomes monstrous.)
When this creature becomes monstrous, tap up to four target creatures. Those creatures don't untap during their controllers' untap steps for as long as you control this creature.

Coral Merfolk

Grisly Anglerfish

{6}: Creatures your opponents control attack this turn if able.

Grizzled Angler

{T}: Mill two cards. Then if there is a colorless creature card in your graveyard, transform this creature. (To mill two cards, put the top two cards of your library into your graveyard.)

Grizzled Angler // Grisly Anglerfish

Rishadan Airship

Shipwreck Marsh

This land enters tapped unless you control two or more other lands.
{T}: Add {U} or {B}.

Dalakos, Crafter of Wonders

{T}: Add {C}{C}. Spend this mana only to cast artifact spells or activate abilities of artifacts.
Equipped creatures you control have flying and haste.

Merrow Grimeblotter

{1}{U/B}, {Q}: Target creature gets -2/-0 until end of turn. ({Q} is the untap symbol.)

Kukemssa Pirates

Whenever this creature attacks and isn't blocked, you may gain control of target artifact defending player controls. If you do, this creature assigns no combat damage this turn.

Coral Commando

Angrath, Minotaur Pirate

+2: Angrath deals 1 damage to target opponent or planeswalker and each creature that player or that planeswalker's controller controls.
−3: Return target Pirate card from your graveyard to the battlefield.
−11: Destroy all creatures target opponent controls. Angrath deals damage to that player equal to their total power.

Shipwreck Sifters

When this creature enters, draw a card, then discard a card.
Whenever you discard a Spirit card or a card with disturb, put a +1/+1 counter on this creature.

Prosperous Pirates

When this creature enters, create two Treasure tokens. (They're artifacts with "{T}, Sacrifice this token: Add one mana of any color.")

Pirate's Cutlass

When this Equipment enters, attach it to target Pirate you control.
Equipped creature gets +2/+1.
Equip {2} ({2}: Attach to target creature you control. Equip only as a sorcery.)

Mire Triton

Deathtouch
When this creature enters, mill two cards and you gain 2 life. (To mill a card, put the top card of your library into your graveyard.)

Shipwreck Singer

Flying
{1}{U}: Target creature an opponent controls attacks this turn if able.
{1}{B}, {T}: Attacking creatures get -1/-1 until end of turn.

Dreadship Reef

{T}: Add {C}.
{1}, {T}: Put a storage counter on this land.
{1}, Remove X storage counters from this land: Add X mana in any combination of {U} and/or {B}.

Glimmerbell

Darting Merfolk

{U}: Return this creature to its owner's hand.

Golden Egg

When this artifact enters, draw a card.
{1}, {T}, Sacrifice this artifact: Add one mana of any color.
{2}, {T}, Sacrifice this artifact: You gain 3 life.

Tolarian Kraken

Whenever you draw a card, you may pay {1}. When you do, you may tap or untap target creature.

Merrow Bonegnawer

{T}: Target player exiles a card from their graveyard.
Whenever you cast a black spell, you may untap this creature.

Arctic Merfolk

Kicker—Return a creature you control to its owner's hand. (You may return a creature you control to its owner's hand in addition to any other costs as you cast this spell.)
If this creature was kicked, it enters with a +1/+1 counter on it.

Kraken Hatchling

Shipwreck Dowser

Prowess (Whenever you cast a noncreature spell, this creature gets +1/+1 until end of turn.)
When this creature enters, return target instant or sorcery card from your graveyard to your hand.

Leechridden Swamp

({T}: Add {B}.)
This land enters tapped.
{B}, {T}: Each opponent loses 1 life. Activate only if you control two or more black permanents.

Death Charmer

Whenever this creature deals combat damage to a creature, that creature's controller loses 2 life unless they pay {2}.

Hanweir, the Writhing Township

Trample, haste
Whenever Hanweir attacks, create two 3/2 colorless Eldrazi Horror creature tokens that are tapped and attacking.

Glimmerpost

When this land enters, you gain 1 life for each Locus on the battlefield.
{T}: Add {C}.