Diminish

Target creature has base power and toughness 1/1 until end of turn.

Giant Octopus

Wayfarer's Bauble

{2}, {T}, Sacrifice this artifact: Search your library for a basic land card, put that card onto the battlefield tapped, then shuffle.

Tromokratis

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.)

Polar Kraken

Trample
This creature enters tapped.
Cumulative upkeep—Sacrifice a land. (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.)

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.

Sol Ring

Inkwell Leviathan

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.)

Sea-Dasher Octopus

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.

Trench Behemoth

Return a land you control to its owner's hand: Untap this creature. It gains hexproof until end of turn.
Landfall — Whenever a land you control enters, target creature an opponent controls attacks during its controller's next combat phase if able.

Benthic Behemoth

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

Rhystic Study

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

Soldevi Excavations

If this land would enter, sacrifice an untapped Island instead. If you do, put this land onto the battlefield. If you don't, put it into its owner's graveyard.
{T}: Add {C}{U}.
{1}, {T}: Scry 1.

Strip Mine

{T}: Add {C}.
{T}, Sacrifice this land: Destroy target land.

Kasmina's Transmutation

Enchant creature
Enchanted creature loses all abilities and has base power and toughness 1/1.

Halimar Depths

This land enters tapped.
When this land enters, look at the top three cards of your library, then put them back in any order.
{T}: Add {U}.

Crush of Tentacles

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.

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.

Stormsurge Kraken

Hexproof
Lieutenant — As long as you control your commander, this creature gets +2/+2 and has "Whenever this creature becomes blocked, you may draw two cards."

Lorthos, the Tidemaker

Whenever Lorthos 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.

Crucible of Worlds

Traumatic Visions

Counter target spell.
Basic landcycling {1}{U} ({1}{U}, Discard this card: Search your library for a basic land card, reveal it, put it into your hand, then shuffle.)

Jokulmorder

Trample
This creature enters tapped.
When this creature enters, sacrifice it unless you sacrifice five lands.
This creature doesn't untap during your untap step.
Whenever you play an Island, you may untap this creature.

Quest for Ula's Temple

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

Terrain Generator

{T}: Add {C}.
{2}, {T}: You may put a basic land card from your hand onto the battlefield tapped.

Thawing Glaciers

This land enters tapped.
{1}, {T}: Search your library for a basic land card, put that card onto the battlefield tapped, then shuffle. Return this land to its owner's hand at the beginning of the next cleanup step.

Elder Deep-Fiend

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.

Kederekt Leviathan

When this creature enters, 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.)

Kiora Bests the Sea God

(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.

Time Spiral

Exile Time Spiral. Each player shuffles their hand and graveyard into their library, then draws seven cards. You untap up to six lands.

Rogue's Passage

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

Miren, the Moaning Well

{T}: Add {C}.
{3}, {T}, Sacrifice a creature: You gain life equal to the sacrificed creature's toughness.

Lodestone Bauble

{1}, {T}, Sacrifice this artifact: Put up to four target basic land cards from a player's graveyard on top of their library in any order. That player draws a card at the beginning of the next turn's upkeep.

Displacement Wave

Return all nonland permanents with mana value X or less to their owners' hands.

Soothsaying

{3}{U}{U}: Shuffle your library.
{X}: Look at the top X cards of your library, then put them back in any order.

Charix, the Raging Isle

Spells your opponents cast that target Charix cost {2} more to cast.
{3}: Charix gets +X/-X until end of turn, where X is the number of Islands you control.

Whelming Wave

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

Grozoth

Defender (This creature can't attack.)
When this creature enters, you may search your library for any number of cards that have mana value 9, reveal them, put them into your hand, then shuffle.
{4}: This creature loses defender until end of turn.
Transmute {1}{U}{U} ({1}{U}{U}, Discard this card: Search your library for a card with the same mana value as this card, reveal it, put it into your hand, then shuffle. Transmute only as a sorcery.)

Engulf the Shore

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

Call to the Kindred

Enchant creature
At the beginning of your upkeep, you may look at the top five cards of your library. If you do, you may put a creature card that shares a creature type with enchanted creature from among them onto the battlefield, then you put the rest of those cards on the bottom of your library in any order.

Slinn Voda, the Rising Deep

Kicker {1}{U} (You may pay an additional {1}{U} as you cast this spell.)
When Slinn Voda enters, if it was kicked, return all creatures to their owners' hands except for Merfolk, Krakens, Leviathans, Octopuses, and Serpents.

Omen of the Sea

Flash (You may cast this spell any time you could cast an instant.)
When this enchantment enters, scry 2, then draw a card.
{2}{U}, Sacrifice this enchantment: 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.)

Time Reversal

Each player shuffles their hand and graveyard into their library, then draws seven cards. Exile Time Reversal.

Theft of Dreams

Draw a card for each tapped creature target opponent controls.

Ugin's Insight

Scry X, where X is the highest mana value among permanents you control, then draw three cards.

Thing from the Deep

Whenever this creature attacks, sacrifice it unless you sacrifice an Island.

Bident of Thassa

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.

Scourge of Fleets

When this creature enters, 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.

Kukemssa Serpent

This creature can't attack unless defending player controls an Island.
{U}, Sacrifice an Island: Target land an opponent controls becomes an Island until end of turn.
When you control no Islands, sacrifice this creature.

Breaching Leviathan

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

Sensei's Divining Top

{1}: Look at the top three cards of your library, then put them back in any order.
{T}: Draw a card, then put this artifact on top of its owner's library.

Thassa, God of the Sea

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.

Dizzy Spell

Target creature gets -3/-0 until end of turn.
Transmute {1}{U}{U} ({1}{U}{U}, Discard this card: Search your library for a card with the same mana value as this card, reveal it, put it into your hand, then shuffle. Transmute only as a sorcery.)

Kraken of the Straits

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

Long-Term Plans

Search your library for a card, then shuffle and put that card third from the top.

Nevinyrral's Disk

This artifact enters tapped.
{1}, {T}: Destroy all artifacts, creatures, and enchantments.

Retraced Image

Reveal a card in your hand, then put that card onto the battlefield if it has the same name as a permanent.

Spawning Kraken

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

Mitotic Manipulation

Look at the top seven cards of your library. You may put one of those cards onto the battlefield if it has the same name as a permanent. Put the rest on the bottom of your library in any order.

Kefnet's Monument

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.

Sapphire Medallion

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

Armillary Sphere

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

Serpent of Yawning Depths

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

Foresee

Octoprophet

When this creature enters, 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.)

Fabricate

Search your library for an artifact card, reveal it, put it into your hand, then shuffle.

Kraken Hatchling

Reliquary Tower

You have no maximum hand size.
{T}: Add {C}.

Interpret the Signs

Scry 3, then reveal the top card of your library. Draw cards equal to that card's mana value. (To scry 3, look at the top three cards of your library, then put any number of them on the bottom and the rest on top in any order.)

Expedition Map

{2}, {T}, Sacrifice this artifact: Search your library for a land card, reveal it, put it into your hand, then shuffle.

Keep Watch

Soaring Seacliff

This land enters tapped.
When this land enters, target creature gains flying until end of turn.
{T}: Add {U}.

Snow-Covered Island

Nykthos, Shrine to Nyx

{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.)