{T}: Add one mana of any color in your commander's color identity. Sacrifice Commander's Sphere: Draw a card.

Equipped creature has vigilance, trample, and haste. Equip {1} ({1}: Attach to target creature you control. Equip only as a sorcery.)

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.

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

Equipped creature gets +1/+1 and has trample and lifelink. {1}: Permanents your opponents control lose hexproof and indestructible until end of turn. Equip {2}

Sky Diamond enters the battlefield tapped. {T}: Add {U}.

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

Whenever you cast a blue spell or an Island enters the battlefield under your control, you gain 1 life.

Equipped creature has hexproof and haste. (It can't be the target of spells or abilities your opponents control.) Equip {1}

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}

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

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.

Flash

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

Defender When Hightide Hermit enters the battlefield, you get {E}{E}{E}{E} (four energy counters). Pay {E}{E}: Hightide Hermit can attack this turn as though it didn't have defender.

Flash This spell can't be countered. Whenever you cast a spell, choose up to one — • Return target spell you don't control to its owner's hand. • Return target nonland permanent to its owner's hand.

Whenever another snow permanent enters the battlefield under your control, you may have target player mill two cards.

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}.

Flying When Mulldrifter enters the battlefield, draw two cards. Evoke {2}{U} (You may cast this spell for its evoke cost. If you do, it's sacrificed when it enters the battlefield.)

When Purple-Crystal Crab dies, draw a card.

Landfall — Whenever a land enters the battlefield under your control, each opponent mills three cards. (To mill a card, a player puts the top card of their library into their graveyard.)

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.

{2}{U}: Adapt 2. (If this creature has no +1/+1 counters on it, put two +1/+1 counters on it.)

{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 the battlefield, you may search your library for a basic land card, reveal it, put it into your hand, then shuffle.

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

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.

Indestructible As long as your devotion to blue is less than five, Thassa isn't a creature. (Each {U} in the mana costs of permanents you control counts toward your devotion to blue.) At the beginning of your upkeep, scry 1. {1}{U}: Target creature you control can't be blocked this turn.

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.)

Enchant creature Enchanted creature loses all abilities and is a blue Fish with base power and toughness 0/1.

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

Whenever Marit Lage's Slumber or another snow permanent enters the battlefield under your control, scry 1. At the beginning of your upkeep, if you control ten or more snow permanents, sacrifice Marit Lage's Slumber. If you do, create Marit Lage, a legendary 20/20 black Avatar creature token with flying and indestructible.

As Monastery Siege enters the battlefield, choose Khans or Dragons. • Khans — At the beginning of your draw step, draw an additional card, then discard a card. • Dragons — Spells your opponents cast that target you or a permanent you control cost {2} more to cast.

Flash When Omen of the Sea enters the battlefield, scry 2, then draw a card. {2}{U}, Sacrifice Omen of the Sea: Scry 2.

Landfall — Whenever a land enters the battlefield under your control, choose one — • You may tap or untap target creature. • Scry 1. (Look at the top card of your library. You may put that card on the bottom of your library.)

{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.

Look at the top three cards of your library. Put one of them into your hand and the rest on the bottom of your library in any order.

Draw two cards, then discard a card.

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

Look at the top four cards of your library. Put one of them into your hand and the rest on the bottom of your library in any order.

Choose one — • Counter target spell unless its controller pays {3}. • Look at the top four cards of your library. Put one of them into your hand and the rest on the bottom of your library in any order.

Return target creature to its owner's hand. If that creature is attacking, you may put it on top of its owner's library instead.

Look at the top three cards of your library. Put one of those cards into your hand, one on top of your library, and one on the bottom of your library.

{T}: Add {C}. {1}, {T}, Sacrifice Bant Panorama: Search your library for a basic Forest, Plains, or Island card, put it onto the battlefield tapped, then shuffle.

Castle Vantress enters the battlefield tapped unless you control an Island. {T}: Add {U}. {2}{U}{U}, {T}: Scry 2.

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}.

Desert of the Mindful enters the battlefield tapped. {T}: Add {U}. Cycling {1}{U} ({1}{U}, Discard this card: Draw a card.)

{T}: Add {C}. {1}, {T}, Sacrifice Esper Panorama: Search your library for a basic Plains, Island, or Swamp card, put it onto the battlefield tapped, then shuffle.

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

{T}: Add {C}. {1}, {T}, Sacrifice Grixis Panorama: Search your library for a basic Island, Swamp, or Mountain card, put it onto the battlefield tapped, then shuffle.

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}.

Lonely Sandbar enters the battlefield tapped. {T}: Add {U}. Cycling {U} ({U}, Discard this card: Draw a card.)

When Maestros Theater enters the battlefield, sacrifice it. When you do, search your library for a basic Island, Swamp, or Mountain card, put it onto the battlefield tapped, then shuffle and you gain 1 life.

Memorial to Genius enters the battlefield tapped. {T}: Add {U}. {4}{U}, {T}, Sacrifice Memorial to Genius: Draw two cards.

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.

When Obscura Storefront enters the battlefield, sacrifice it. When you do, search your library for a basic Plains, Island, or Swamp card, put it onto the battlefield tapped, then shuffle and you gain 1 life.

Remote Isle enters the battlefield tapped. {T}: Add {U}. Cycling {2} ({2}, Discard this card: Draw a card.)

{T}: Add {C}. {4}, {T}: Target creature can't be blocked this turn.

Skyline Cascade enters the battlefield tapped. When Skyline Cascade enters the battlefield, target creature an opponent controls doesn't untap during its controller's next untap step. {T}: Add {U}.

({T}: Add {U}.)

Soaring Seacliff enters the battlefield tapped. When Soaring Seacliff enters the battlefield, target creature gains flying until end of turn. {T}: Add {U}.

+1: Scry 1, then draw a card. −2: Return target creature to its owner's hand. −8: You get an emblem with "Whenever an opponent casts their first spell each turn, counter that spell."

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.

+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.

Return target creature to its owner's hand. Draw a card.

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.")

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

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.)

Scry 2, then draw a card. Flashback {4}{U} (You may cast this card from your graveyard for its flashback cost. Then exile it.)

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.)