Command Tower

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

Undercity Sewers

({T}: Add {U} or {B}.)
This land enters tapped.
When this land enters, surveil 1. (Look at the top card of your library. You may put it into your graveyard.)

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.

Spectral Deluge

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.)

Kozilek's Unsealing

Devoid (This card has no color.)
Whenever you cast a creature spell with mana value 4, 5, or 6, create two 0/1 colorless Eldrazi Spawn creature tokens with "Sacrifice this token: Add {C}."
Whenever you cast a creature spell with mana value 7 or greater, draw three cards.

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.

Aetherspouts

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

Krothuss, Lord of the Deep

Flying
Whenever Krothuss attacks, create a tapped and attacking token that's a copy of another target attacking creature. If that creature is a Kraken, Leviathan, Octopus, or Serpent, create two of those tokens instead.

Runo Stromkirk

Flying
When Runo enters, put up to one target creature card from your graveyard on top of your library.
At the beginning of your upkeep, look at the top card of your library. You may reveal that card. If a creature card with mana value 6 or greater is revealed this way, transform Runo.

Runo Stromkirk // Krothuss, Lord of the Deep

Hullbreaker Horror

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.

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.

Deepchannel Mentor

Blue creatures you control can't be blocked.

Nezahal, Primal Tide

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. Return it to the battlefield tapped under its owner's control at the beginning of the next end step.

Defiler of Dreams

Flying
As an additional cost to cast blue permanent spells, you may pay 2 life. Those spells cost {U} less to cast if you paid life this way. This effect reduces only the amount of blue mana you pay.
Whenever you cast a blue permanent spell, draw a card.

Stormtide Leviathan

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.

Island

Scour from Existence

Serpent of Yawning Depths

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

Junk Winder

Affinity for tokens (This spell costs {1} less to cast for each token you control.)
Whenever a token you control enters, tap target nonland permanent an opponent controls. It doesn't untap during its controller's next untap step.

Thieving Skydiver

Kicker {X}. X can't be 0. (You may pay an additional {X} as you cast this spell.)
Flying
When this creature enters, if it was kicked, gain control of target artifact with mana value X or less. If that artifact is an Equipment, attach it to this creature.

Thirst for Meaning

Draw three cards. Then discard two cards unless you discard an enchantment card.

Sol Ring

Victimize

Choose two target creature cards in your graveyard. Sacrifice a creature. If you do, return the chosen cards to the battlefield tapped.

Inundated Archive

This land enters tapped.
{T}: Add {U} or {B}.

Waterlogged Teachings

Search your library for an instant card or a card with flash, reveal it, put it into your hand, then shuffle.

Waterlogged Teachings // Inundated Archive

Reconnaissance Mission

Whenever a creature you control deals combat damage to a player, you may draw a card.
Cycling {2} ({2}, Discard this card: Draw a card.)

Whelming Wave

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

The Celestus

If it's neither day nor night, it becomes day as The Celestus enters.
{T}: Add one mana of any color.
{3}, {T}: If it's night, it becomes day. Otherwise, it becomes night. Activate only as a sorcery.
Whenever day becomes night or night becomes day, you gain 1 life. You may draw a card. If you do, discard a card.

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.

Qarsi Revenant

Flying, deathtouch, lifelink
Renew — {2}{B}, Exile this card from your graveyard: Put a flying counter, a deathtouch counter, and a lifelink counter on target creature. Activate only as a sorcery.

Sleep

Tap all creatures target player controls. Those creatures don't untap during that player's next untap step.

Quicksilver Fountain

At the beginning of each player's upkeep, that player puts a flood counter on target non-Island land they control of their choice. That land is an Island for as long as it has a flood counter on it.
At the beginning of each end step, if all lands on the battlefield are Islands, remove all flood counters from them.

Curse of the Swine

Exile X target creatures. For each creature exiled this way, its controller creates a 2/2 green Boar creature token.

Wash Out

Return all permanents of the color of your choice to their owners' hands.

Polluted Delta

{T}, Pay 1 life, Sacrifice this land: Search your library for an Island or Swamp card, put it onto the battlefield, then shuffle.

Contaminated Aquifer

({T}: Add {U} or {B}.)
This land enters tapped.

Arcane Signet

The Immortal Sun

Players can't activate planeswalkers' loyalty abilities.
At the beginning of your draw step, draw an additional card.
Spells you cast cost {1} less to cast.
Creatures you control get +1/+1.

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."

Fetid Pools

({T}: Add {U} or {B}.)
This land enters tapped.
Cycling {2} ({2}, Discard this card: Draw a card.)

Aether Gale

Return six target nonland permanents to their owners' hands.

Swiftfoot Boots

Equipped creature has hexproof and haste. (It can't be the target of spells or abilities your opponents control. It can attack and {T} no matter when it came under your control.)
Equip {1} ({1}: Attach to target creature you control. Equip only as a sorcery.)

Consecrated Sphinx

Flying
Whenever an opponent draws a card, you may draw two cards.

Starwinder

Whenever a creature you control deals combat damage to a player, you may draw that many cards.
Warp {2}{U}{U} (You may cast this card from your hand for its warp cost. Exile this creature at the beginning of the next end step, then you may cast it from exile on a later turn.)

Benthic Anomaly

Devoid (This card has no color.)
When you cast this spell, for each opponent, choose a creature that player controls. Create a token that's a copy of one of those creatures, except its power is equal to the total power of those creatures, its toughness is equal to the total toughness of those creatures, and it's a colorless Eldrazi creature.

Sunken Ruins

{T}: Add {C}.
{U/B}, {T}: Add {U}{U}, {U}{B}, or {B}{B}.

Thada Adel, Acquisitor

Islandwalk (This creature can't be blocked as long as defending player controls an Island.)
Whenever Thada Adel deals combat damage to a player, search that player's library for an artifact card and exile it. Then that player shuffles. Until end of turn, you may play that card.

Myriad Landscape

This land enters tapped.
{T}: Add {C}.
{2}, {T}, Sacrifice this land: Search your library for up to two basic land cards that share a land type, put them onto the battlefield tapped, then shuffle.

Conduit of Ruin

When you cast this spell, you may search your library for a colorless creature card with mana value 7 or greater, reveal it, then shuffle and put that card on top.
The first creature spell you cast each turn costs {2} less to cast.

Watery Grave

({T}: Add {U} or {B}.)
As this land enters, you may pay 2 life. If you don't, it enters tapped.

Flare of Malice

You may sacrifice a nontoken black creature rather than pay this spell's mana cost.
Each opponent sacrifices a creature or planeswalker with the greatest mana value among creatures and planeswalkers they control.

Soul Shatter

Each opponent sacrifices a creature or planeswalker with the greatest mana value among creatures and planeswalkers they control.

Aetherize

Return all attacking creatures to their owner's hand.

Sunken Hollow

({T}: Add {U} or {B}.)
This land enters tapped unless you control two or more basic lands.

Dimir Signet

Thryx, the Sudden Storm

Flash (You may cast this spell any time you could cast an instant.)
Flying
Spells you cast with mana value 5 or greater cost {1} less to cast and can't be countered.

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.)

Drowned Catacomb

This land enters tapped unless you control an Island or a Swamp.
{T}: Add {U} or {B}.

Rejoin the Fight

Mill three cards. Then starting with the next opponent in turn order, each opponent chooses a creature card in your graveyard that hasn't been chosen. Return each card chosen this way to the battlefield under your control.

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.

Thirst for Knowledge

Draw three cards. Then discard two cards unless you discard an artifact card.

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.

Reliquary Tower

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

Grappling Kraken

Landfall — Whenever a land you control enters, tap target creature an opponent controls and put a stun counter on it. (If a permanent with a stun counter would become untapped, remove one from it instead.)

Steel Hellkite

Flying
{2}: This creature gets +1/+0 until end of turn.
{X}: Destroy each nonland permanent with mana value X whose controller was dealt combat damage by this creature this turn. Activate only once each turn.

Likeness Looter

Flying
{T}: Draw a card, then discard a card.
{X}: This creature becomes a copy of target creature card in your graveyard with mana value X, except it has flying and this ability. Activate only as a sorcery.

Cyclonic Rift

Return target nonland permanent you don't control to its owner's hand.
Overload {6}{U} (You may cast this spell for its overload cost. If you do, change "target" in its text to "each.")

Swamp

Reservoir Kraken

Trample, ward {2}
At the beginning of each combat, if this creature is untapped, any opponent may tap an untapped creature they control. If they do, tap this creature and create a 1/1 blue Fish creature token with "This token can't be blocked."

Collector's Vault

{2}, {T}: Draw a card, then discard a card. Create a Treasure token. (It's an artifact with "{T}, Sacrifice this token: Add one mana of any color.")

Bonders' Enclave

{T}: Add {C}.
{3}, {T}: Draw a card. Activate only if you control a creature with power 4 or greater.

Ominous Seas

Whenever you draw a card, put a foreshadow counter on this enchantment.
Remove eight foreshadow counters from this enchantment: Create an 8/8 blue Kraken creature token.
Cycling {2} ({2}, Discard this card: Draw a card.)

Rune-Scarred Demon

Flying
When this creature enters, search your library for a card, put it into your hand, then shuffle.

Cone of Cold

Roll a d20.
1—9 | Tap all creatures your opponents control.
10—19 | Tap all creatures your opponents control. Those creatures don't untap during their controllers' next untap steps.
20 | Tap all creatures your opponents control. Those creatures don't untap during their controllers' next untap steps. Until your next turn, creatures your opponents control enter tapped.

The Reality Chip

You may look at the top card of your library any time.
As long as The Reality Chip is attached to a creature, you may play lands and cast spells from the top of your library.
Reconfigure {2}{U} ({2}{U}: Attach to target creature you control; or unattach from a creature. Reconfigure only as a sorcery. While attached, this isn't a creature.)

Mind Stone

{T}: Add {C}.
{1}, {T}, Sacrifice this artifact: Draw a card.

Thought Vessel

Sapphire Medallion

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

Meteor Golem

When this creature enters, destroy target nonland permanent an opponent controls.

Temple of the False God

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

Lightning Greaves

Equipped creature has haste and shroud. (It can't be the target of spells or abilities.)
Equip {0}

Summon: Leviathan

(As this Saga enters and after your draw step, add a lore counter. Sacrifice after III.)
I — Return each creature that isn't a Kraken, Leviathan, Merfolk, Octopus, or Serpent to its owner's hand.
II, III — Until end of turn, whenever a Kraken, Leviathan, Merfolk, Octopus, or Serpent attacks, draw a card.
Ward {2}

Shipwreck Marsh

This land enters tapped unless you control two or more other lands.
{T}: Add {U} or {B}.

Bag of Holding

Whenever you discard a card, exile that card from your graveyard.
{2}, {T}: Draw a card, then discard a card.
{4}, {T}, Sacrifice this artifact: Return all cards exiled with this artifact to their owner's hand.