You may play an additional land on each of your turns.

Landfall -- Whenever a land you control enters, you may draw a card.

Arixmethes, Slumbering Isle enters the battlefield tapped with five slumber counters on it.

As long as Arixmethes has a slumber counter on it, it's a land. (It's not a creature.)

Whenever you cast a spell, you may remove a slumber counter from Arixmethes.

{T}: Add {G}{U}.

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.

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.

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.)

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.

You may play an additional land on each of your turns.

({T}: Add {G}.)

({T}: Add {G}.)

({T}: Add {G}.)

({T}: Add {G}.)

({T}: Add {G}.)

When Great Whale enters the battlefield, untap up to seven lands.

Hinterland Harbor enters tapped unless you control a Forest or an Island.

{T}: Add {G} or {U}.

When you cast this spell, you gain half X life and draw half X cards. Round down each time.

Flying, trample

Hydroid Krasis enters the battlefield with X +1/+1 counters on it.

({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}: Untap another target permanent.

Whenever a creature you control with power 4 or greater enters, draw a card.

-1: Untap target permanent.

+1: Untap up to one target creature and up to one target land.

-2: Reveal the top four cards of your library. You may put a creature card and/or a land card from among them into your hand. Put the rest into your graveyard.

-8: You get an emblem with "Whenever a creature enters the battlefield under your control, you may have it fight target creature." Then create three 8/8 blue Octopus creature tokens.

+1: Until your next turn, prevent all damage that would be dealt to and dealt by target permanent an opponent controls.

-1: Draw a card. You may play an additional land this turn.

-5: You get an emblem with "At the beginning of your end step, create a 9/9 blue Kraken creature token."

This spell can't be countered.

At the beginning of each upkeep, create a 3/3 blue Serpent creature token named Koma's Coil.

Sacrifice another Serpent: Choose one --

• Tap target permanent. Its activated abilities can't be activated this turn.

• Koma, Cosmos Serpent gains indestructible until end of turn.

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.

Whenever you draw a card, put a foreshadow counter on Ominous Seas.

Remove eight foreshadow counters from Ominous Seas: Create an 8/8 blue Kraken creature token.

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

Flying

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

Enchant creature

Enchanted creature gets -6/-0.

Trample

Polar Kraken enters the battlefield 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.)

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.'"

Return up to three target creatures and/or enchantments to their owners' hands.

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.

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

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

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

Enchant land

When Spreading Seas enters, draw a card.

Enchanted land is an Island.

Target creature gets +2/+2 until end of turn. You may put a land card from your hand onto the battlefield.

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

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.

{4}: Scry 1, then reveal the top card of your library. If it's a land card, put it onto the battlefield tapped. Otherwise, draw a card.

Partner (You can have two commanders if both have partner.)

Any player may cast spells as though they had flash.

Your opponents can't cast spells during your turn.

Create a 5/5 blue Wall creature token with defender. Sacrifice it at the beginning of the next end step.

Enchant creature

Enchanted creature gets -6/-0 and loses flying.

Return target creature to its owner's hand. Scry 1. (Look at the top card of your library. You may put that card on the bottom of your library.)

Defender (This creature can't attack.)

{U}{U}, {T}: Create a 0/1 blue Plant Wall creature token with defender named Kelp.

{T}, Pay 1 life: Add {G} or {U}.

{1}, {T}, Sacrifice Waterlogged Grove: Draw a card.

Flying

When Wavesifter enters the battlefield, investigate twice. (To investigate, create a Clue token. It's an artifact with "{2}, Sacrifice this artifact: Draw a card.")

Evoke {G}{U} (You may cast this spell for its evoke cost. If you do, it's sacrificed when it enters the battlefield.)

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

Woodland Stream enters the battlefield tapped.

{T}: Add {G} or {U}.