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

{2}, {T}, Sacrifice Armillary Sphere: Search your library for up to two basic land cards, reveal them, put them into your hand, then shuffle.

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.

Target player draws X cards. Shuffle Blue Sun's Zenith into its owner's library.

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

When Breaching Leviathan enters the battlefield, if you cast it from your hand, tap all nonblue creatures. Those creatures don't untap during their controllers' next untap steps.

Create a token that's a copy of target creature you control.

Flashback {5}{U}{U} (You may cast this card from your graveyard for its flashback cost. Then exile it.)

As Caged Sun enters the battlefield, choose a color.

Creatures you control of the chosen color get +1/+1.

Whenever a land's ability causes you to add one or more mana of the chosen color, add one additional mana of that color.

Castle Vantress enters the battlefield tapped unless you control an Island.

{T}: Add {U}.

{2}{U}{U}, {T}: Scry 2.

Whenever you draw a card, put a +1/+1 counter on Chasm Skulker.

When Chasm Skulker dies, create X 1/1 blue Squid creature tokens with islandwalk, where X is the number of +1/+1 counters on Chasm Skulker. (They can't be blocked as long as defending player controls an Island.)

Islandwalk (This creature can't be blocked as long as defending player controls an Island.)

Whenever Colossal Whale attacks, you may exile target creature defending player controls until Colossal Whale leaves the battlefield. (That creature returns under its owner's control.)

Coral Atoll enters the battlefield tapped.

When Coral Atoll enters the battlefield, sacrifice it unless you return an untapped Island you control to its owner's hand.

{T}: Add {C}{U}.

Counter target spell.

Surge {3}{U}{U} (You may cast this spell for its surge cost if you or a teammate has cast another spell this turn.)

Return all nonland permanents to their owners' hands. If this spell's surge cost was paid, create an 8/8 blue Octopus creature token.

Return target nonland permanent you don't control to its owner's hand.

Overload {6}{U} (You may cast this spell for its overload cost. If you do, change "target" in its text to "each.")

Deep-Sea Kraken can't be blocked.

Suspend 9--{2}{U} (Rather than cast this card from your hand, you may pay {2}{U} and exile it with nine time counters on it. At the beginning of your upkeep, remove a time counter. When the last is removed, cast it without paying its mana cost. It has haste.)

Whenever an opponent casts a spell, if Deep-Sea Kraken is suspended, remove a time counter from it.

Counter target spell.

Draw a card.

Counter target spell. If that spell is countered this way, exile it instead of putting it into its owner's graveyard.

Counter target spell. Scry 1. (Look at the top card of your library. You may put that card on the bottom of your library.)

Draw two cards.

Flash

Emerge {5}{U}{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, tap up to four target permanents.

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

Multikicker {2} (You may pay an additional {2} any number of times as you cast this spell.)

Everflowing Chalice enters the battlefield with a charge counter on it for each time it was kicked.

{T}: Add {C} for each charge counter on Everflowing Chalice.

Reveal the top five cards of your library. An opponent separates those cards into two piles. Put one pile into your hand and the other into your graveyard.

Whenever Fleet Swallower attacks, target player mills half their library, rounded up.

{U}{U}: Tap target creature without flying.

Draw a card for each Island you control.

{T}: Add three mana of any one color.

Halimar Depths enters the battlefield tapped.

When Halimar Depths enters the battlefield, look at the top three cards of your library, then put them back in any order.

{T}: Add {U}.

{T}: Add {C}{C}.

{2}, {T}, Sacrifice Hedron Archive: Draw two cards.

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

Enchant creature, land, or planeswalker

Enchanted permanent is a colorless land with "{T}: Add {C}" and loses all other card types and abilities.

Trample

Islandwalk (This creature can't be blocked as long as defending player controls an Island.)

Shroud (This creature can't be the target of spells or abilities.)

Kicker {1}{U} (You may pay an additional {1}{U} as you cast this spell.)

Return target nonland permanent to its owner's hand. If this spell was kicked, draw a card.

Return all nonblue creatures to their owners' hands.

({T}: Add {U}.)

({T}: Add {U}.)

({T}: Add {U}.)

({T}: Add {U}.)

({T}: Add {U}.)

({T}: Add {U}.)

({T}: Add {U}.)

({T}: Add {U}.)

({T}: Add {U}.)

({T}: Add {U}.)

({T}: Add {U}.)

({T}: Add {U}.)

({T}: Add {U}.)

({T}: Add {U}.)

({T}: Add {U}.)

({T}: Add {U}.)

({T}: Add {U}.)

({T}: Add {U}.)

({T}: Add {U}.)

({T}: Add {U}.)

({T}: Add {U}.)

({T}: Add {U}.)

({T}: Add {U}.)

({T}: Add {U}.)

({T}: Add {U}.)

({T}: Add {U}.)

({T}: Add {U}.)

({T}: Add {U}.)

({T}: Add {U}.)

Draw two cards. If you control a Jace planeswalker, draw three cards instead.

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.

Creatures with power less than the number of Islands you control can't block Kraken of the Straits.

Equipped creature has haste and shroud. (It can't be the target of spells or abilities.)

Equip {0}

Lonely Sandbar enters the battlefield tapped.

{T}: Add {U}.

Cycling {U} ({U}, Discard this card: Draw a card.)

Whenever Lorthos, the Tidemaker attacks, you may pay {8}. If you do, tap up to eight target permanents. Those permanents don't untap during their controllers' next untap steps.

When Mesmerizing Benthid enters the battlefield, create two 0/2 blue Illusion creature tokens with "Whenever this creature blocks a creature, that creature doesn't untap during its controller's next untap step."

Mesmerizing Benthid has hexproof as long as you control an Illusion.

{T}: Add {C}.

{1}, {T}, Sacrifice Mind Stone: Draw a card.

Myriad Landscape enters the battlefield tapped.

{T}: Add {C}.

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

({T}: Add {U}.)

Mystic Sanctuary enters the battlefield tapped unless you control three or more other Islands.

When Mystic Sanctuary enters the battlefield untapped, you may put target instant or sorcery card from your graveyard on top of your library.

Counter target noncreature spell.

This spell can't be countered.

You have no maximum hand size.

Whenever an opponent casts a noncreature spell, draw a card.

Discard three cards: Exile Nezahal, Primal Tide. Return it to the battlefield tapped under its owner's control at the beginning of the next end step.

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

Draw a card.

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

At the beginning of your upkeep, you may look at the top card of your library. If it's a creature card, you may reveal it and put a quest counter on Quest for Ula's Temple.

At the beginning of each end step, if there are three or more quest counters on Quest for Ula's Temple, you may put a Kraken, Leviathan, Octopus, or Serpent creature card from your hand onto the battlefield.

When Reef Worm dies, create a 3/3 blue Fish creature token with "When this creature dies, create a 6/6 blue Whale creature token with 'When this creature dies, create a 9/9 blue Kraken creature token.'"

Remote Isle enters the battlefield tapped.

{T}: Add {U}.

Cycling {2} ({2}, Discard this card: Draw a card.)

Counter target spell. Untap up to four lands.

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

Kicker {5} (You may pay an additional {5} as you cast this spell.)

Create a token that's a copy of target creature. If this spell was kicked, create five of those tokens instead.

Draw cards equal to the highest mana value among permanents you control.

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

When Scourge of Fleets enters the battlefield, 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.

Krakens, Leviathans, Octopuses, and Serpents you control can't be blocked except by Krakens, Leviathans, Octopuses, and Serpents.

{6}{U}{U}: Monstrosity 4. (If this creature isn't monstrous, put four +1/+1 counters on it and it becomes monstrous.)

When Shipbreaker Kraken becomes monstrous, tap up to four target creatures. Those creatures don't untap during their controllers' untap steps for as long as you control Shipbreaker Kraken.

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

Kicker {1}{U} (You may pay an additional {1}{U} as you cast this spell.)

When Slinn Voda, the Rising Deep enters the battlefield, if it was kicked, return all creatures to their owners' hands except for Merfolk, Krakens, Leviathans, Octopuses, and Serpents.

{T}: Add {C}{C}.

Enchant land

When Spreading Seas enters the battlefield, draw a card.

Enchanted land is an Island.

Equipped creature has hexproof and haste. (It can't be the target of spells or abilities your opponents control.)

Equip {1}

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

{T}: Add {C}{C}{C}.

Tromokratis has hexproof unless it's attacking or blocking.

Tromokratis can't be blocked unless all creatures defending player controls block it. (If any creature that player controls doesn't block this creature, it can't be blocked.)

{T}: Add {C}{C}.

Return all creatures to their owners' hands except for Krakens, Leviathans, Octopuses, and Serpents.

Worn Powerstone enters the battlefield tapped.

{T}: Add {C}{C}.