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

Counter target noncreature spell. Its controller creates two Treasure tokens. (They're artifacts with "{T}, Sacrifice this artifact: Add one mana of any color.")

Counter target spell. Its controller may draw up to two cards at the beginning of the next turn's upkeep.

You draw a card at the beginning of the next turn's upkeep.

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

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.

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.

Spells your opponents cast that target Charix, the Raging Isle cost {2} more to cast.

{3}: Charix gets +X/-X until end of turn, where X is the number of Islands you control.

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 Chromeshell Crab is turned face up, you may exchange control of target creature you control and target creature an opponent controls.

You may have Clone enter the battlefield as a copy of any creature on the battlefield.

For each creature target player controls, create a token that's a copy of that creature.

Coldsteel Heart enters the battlefield tapped.

As Coldsteel Heart enters the battlefield, choose a color.

{T}: Add one mana of the chosen color.

Enchant creature

{2}{U}: Untap enchanted creature.

Totem armor (If enchanted creature would be destroyed, instead remove all damage from it and destroy this Aura.)

Flash

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.

Target creature you control gets +0/+3 and gains hexproof until end of turn. (It can't be the target of spells or abilities your opponents control.)

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}: Dreadlight Monstrosity can't be blocked this turn. Activate only if you own a card in exile.

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.)

Drownyard Behemoth has hexproof as long as it entered the battlefield this turn.

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

Draw a card for each Island you control.

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

{T}: Add {C}.

{T}, Sacrifice Ghost Quarter: Destroy target land. Its controller may search their library for a basic land card, put it onto the battlefield, then shuffle.

You may have Glasspool Mimic enter the battlefield as a copy of a creature you control, except it's a Shapeshifter Rogue in addition to its other types.

Glasspool Shore enters the battlefield tapped.

{T}: Add {U}.

Create a 0/3 blue Crab creature token.

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

Landfall -- Whenever a land enters the battlefield under your control, target player mills three cards.

Landfall -- Whenever a land enters the battlefield under your control, Hedron Scrabbler gets +1/+1 until end of turn.

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

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.)

({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}.)

({T}: Add {U}.)

When Kederekt Leviathan enters the battlefield, return all other nonland permanents to their owners' hands.

Unearth {6}{U} ({6}{U}: Return this card from your graveyard to the battlefield. It gains haste. Exile it at the beginning of the next end step or if it would leave the battlefield. Unearth only as a sorcery.)

(As this Saga enters and after your draw step, add a lore counter. Sacrifice after III.)

I -- Create an 8/8 blue Kraken creature token with hexproof.

II -- Tap all nonland permanents target opponent controls. They don't untap during their controller's next untap step.

III -- Gain control of target permanent an opponent controls. Untap it.

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

Equipped creature gets +1/+2 and has hexproof. (It can't be the target of spells or abilities your opponents control.)

Equip {3}

{T}: Add {C}.

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

Mirrorpool enters the battlefield tapped.

{T}: Add {C}.

{2}{C}, {T}, Sacrifice Mirrorpool: Copy target instant or sorcery spell you control. You may choose new targets for the copy.

{4}{C}, {T}, Sacrifice Mirrorpool: Create a token that's a copy of target creature you control.

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 Mirrorshell Crab: Counter target spell or ability unless its controller pays {3}.

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.

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

{2}, {T}, Sacrifice Navigation Orb: Search your library for up to two basic land cards and/or Gate cards, reveal those cards, put one onto the battlefield tapped and the other into your hand, then shuffle.

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

{U}{U}: Attach Neurok Stealthsuit to target creature you control.

Equip {1} ({1}: Attach to target creature you control. Equip only as a sorcery.)

{T}: Add {C}.

{2}, {T}: Choose a color. Add an amount of mana of that color equal to your devotion to that color. (Your devotion to a color is the number of mana symbols of that color in the mana costs of permanents you control.)

Path of Ancestry 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.)

({U/P} can be paid with either {U} or 2 life.)

You may have Phyrexian Metamorph enter the battlefield as a copy of any artifact or creature on the battlefield, except it's an artifact in addition to its other types.

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

When Purple-Crystal Crab dies, draw a card.

Destroy target creature. It can't be regenerated. That creature's controller creates a 3/3 green Frog Lizard creature token.

Exile target creature. Its controller manifests the top card of their library. (That player puts the top card of their library onto the battlefield face down as a 2/2 creature. If it's a creature card, it can be turned face up any time for its mana cost.)

Exile target artifact or creature. Its controller creates a 4/4 blue and red Elemental creature token.

Trample, ward {2}

At the beginning of each combat, if Reservoir Kraken is untapped, any opponent may tap an untapped creature they control. If they do, tap Reservoir Kraken and create a 1/1 blue Fish creature token with "This creature can't be blocked."

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.

Enchant creature (Target a creature as you cast this. This card enters the battlefield attached to that creature.)

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

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.)

You may have Sakashima the Impostor enter the battlefield as a copy of any creature on the battlefield, except its name is Sakashima the Impostor, it's legendary in addition to its other types, and it has "{2}{U}{U}: Return this creature to its owner's hand at the beginning of the next end step."

Choose one. If you control a commander as you cast this spell, you may choose both.

• Target opponent chooses a creature they control. You gain control of it.

• Choose a creature you control. Each other creature you control becomes a copy of that creature until end of turn.

{T}: Add one mana of any color.

{T}: Add three mana of any one color. Activate only if you control three or more lands with the same name.

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.

{T}: Target player exiles a card from their graveyard.

{1}, Sacrifice Scrabbling Claws: Exile target card from a graveyard. Draw a card.

{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.

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.)

{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.

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

As long as Skittering Crustacean is monstrous, it has hexproof. (It can't be the target of spells or abilities your opponents control.)

When Skittering Surveyor enters, you may search your library for a basic land card, reveal it, put it into your hand, then shuffle.

Sky Diamond enters the battlefield tapped.

{T}: Add {U}.

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}.

Whenever a Kraken, Leviathan, Octopus, or Serpent you control deals combat damage to a player, create a 9/9 blue Kraken creature token.

When Specimen Collector enters, create a 1/1 green Squirrel creature token and a 0/3 blue Crab creature token.

When Specimen Collector dies, create a token that's a copy of target token you control.

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.

Foretell {1}{U}{U} (During your turn, you may pay {2} and exile this card from your hand face down. Cast it on a later turn for its foretell cost.)

Star Compass enters tapped.

{T}: Add one mana of any color that a basic land you control could produce.

Hexproof

Lieutenant -- As long as you control your commander, Stormsurge Kraken gets +2/+2 and has "Whenever Stormsurge Kraken becomes blocked, you may draw two cards."

Counter target noncreature spell unless its controller pays {1}.

Ferocious -- If you control a creature with power 4 or greater, counter that spell instead.

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

Equip {1}

{T}: Add {C}.

{1}, {T}, Sacrifice Tectonic Edge: Destroy target nonbasic land. Activate only if an opponent controls four or more lands.

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 Thassa's Emissary or enchanted creature deals combat damage to a player, draw a card.

Enchanted creature gets +3/+3.

You have no maximum hand size.

{T}: Add {C}.

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

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

Return a land you control to its owner's hand: Untap Trench Behemoth. It gains hexproof until end of turn.

Landfall -- Whenever a land enters the battlefield under your control, target creature an opponent controls attacks during its controller's next combat phase if able.

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

Draw a card.

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.

{2}, {T}, Sacrifice Wayfarer's Bauble: Search your library for a basic land card, put that card onto the battlefield tapped, then shuffle.

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

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

Equip {2}

Equipped creature has flying and ward {4}. (Whenever equipped creature becomes the target of a spell or ability an opponent controls, counter it unless that player pays {4}.)

Equip {1}

Worn Powerstone enters the battlefield tapped.

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