Flash

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.

Flash

Ward {2}

Probing Telepathy -- Whenever a creature entering the battlefield under an opponent's control causes a triggered ability of that creature to trigger, you may copy that ability. You may choose new targets for the copy.

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.

Creatures you control have flying.

Creatures your opponents control lose flying and can't have or gain flying.

Defender

When Biolume Egg enters the battlefield, scry 2.

When you sacrifice Biolume Egg, return it to the battlefield transformed under its owner's control at the beginning of the next end step.

Sacrifice two Islands: Biolume Serpent can't be blocked this turn.

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.

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.)

Counter target spell.

At the beginning of your upkeep, look at the top card of your library. You may reveal that card. If an instant or sorcery card is revealed this way, transform Delver of Secrets.

Flying

Counter target spell. Its controller mills three cards.

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

Untap all nonland permanents you control.

Flash

Enchant creature

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

This spell costs {U} less to cast if an opponent cast two or more spells this turn.

Counter target spell.

You may pay 1 life and exile a blue card from your hand rather than pay this spell's mana cost.

Counter target spell.

Enchant creature

Enchanted creature gets +1/+1 and has flying.

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

Counter target creature spell. If it was a legendary spell, the Ring tempts you.

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

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

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.

({T}: Add {U}.)

({T}: Add {U}.)

({T}: Add {U}.)

({T}: Add {U}.)

({T}: Add {U}.)

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({T}: Add {U}.)

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({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}.)

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

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.

Defender (This creature can't attack.)

When Monstrosity of the Lake enters the battlefield, you may pay {5}. If you do, tap all creatures your opponents control, then put a stun counter on each of those creatures. (If a permanent with a stun counter would become untapped, remove one from it instead.)

Islandcycling {2} ({2}, Discard this card: Search your library for an Island card, reveal it, put it into your hand, then shuffle.)

Cumulative upkeep {1} (At the beginning of your upkeep, put an age counter on this permanent, then sacrifice it unless you pay its upkeep cost for each age counter on it.)

Whenever an opponent casts a noncreature spell, you may draw a card unless that player pays {4}.

Search your library for an instant or sorcery card, reveal it, then shuffle and put that card on top.

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.

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.

Nyx Lotus enters the battlefield tapped.

{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.)

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

Draw a card.

Creatures can't attack you unless their controller pays {2} for each creature they control that's attacking you.

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.'"

You have no maximum hand size.

{T}: Add {C}.

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."

When River Herald Scout enters the battlefield, 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.)

{T}: Add {C}.

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

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.)

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.

Mutate {1}{U} (If you cast this spell for its mutate cost, put it over or under target non-Human creature you own. They mutate into the creature on top plus all abilities from under it.)

Flash

Whenever this creature deals combat damage to a player, draw a card.

When you control no Islands, sacrifice Seasinger.

You may choose not to untap Seasinger during your untap step.

{T}: Gain control of target creature whose controller controls an Island for as long as you control Seasinger and Seasinger remains tapped.

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

Serpent of the Endless Sea's power and toughness are each equal to the number of Islands you control.

Serpent of the Endless Sea can't attack unless defending player controls an Island.

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.

Whenever you cast your first spell during each opponent's turn, you may tap or untap target nonland permanent.

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."

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

All lands are Islands in addition to their other types.

Creatures without flying or islandwalk can't attack.

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

Equip {1}

When Thassa's Oracle enters the battlefield, look at the top X cards of your library, where X is your devotion to blue. Put up to one of them on top of your library and the rest on the bottom of your library in a random order. If X is greater than or equal to the number of cards in your library, you win the game. (Each {U} in the mana costs of permanents you control counts toward your devotion to blue.)

Counter target spell unless its controller pays {X}, where X is your devotion to blue. (Each {U} in the mana costs of permanents you control counts toward your devotion to blue.)

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.

Whenever Tidal Terror attacks, you may tap two other untapped creatures you control. If you do, Tidal Terror can't be blocked this turn.

Islandcycling {2} ({2}, Discard this card: Search your library for an Island card, reveal it, put it into your hand, then shuffle.)

Flash

When Voracious Greatshark enters the battlefield, counter target artifact or creature spell.

Cleave {1}{U}{U} (You may cast this spell for its cleave cost. If you do, remove the words in square brackets.)

Counter target spell [that wasn't cast from its owner's hand].

Flying

When Waterwind Scout enters the battlefield, create a Map token. (It's an artifact with "{1}, {T}, Sacrifice this artifact: Target creature you control explores. Activate only as a sorcery.")

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

Flying

As long as Wonder is in your graveyard and you control an Island, creatures you control have flying.