Temple of Mystery

This land enters tapped.
When this land enters, scry 1. (Look at the top card of your library. You may put that card on the bottom.)
{T}: Add {G} or {U}.

Artisan's Sorrow

Destroy target artifact or 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.)

Nissa, Steward of Elements

+2: Scry 2.
0: Look at the top card of your library. If it's a land card or a creature card with mana value less than or equal to the number of loyalty counters on Nissa, you may put that card onto the battlefield.
−6: Untap up to two target lands you control. They become 5/5 Elemental creatures with flying and haste until end of turn. They're still lands.

Crystal Ball

{1}, {T}: 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.)

Whelming Wave

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

Mana Drain

Counter target spell. At the beginning of your next main phase, add an amount of {C} equal to that spell's mana value.

Thassa's Oracle

When this creature enters, 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.)

Hinterland Harbor

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

Training Grounds

Activated abilities of creatures you control cost {2} less to activate. This effect can't reduce the mana in that cost to less than one mana.

Garruk's Uprising

When this enchantment enters, if you control a creature with power 4 or greater, draw a card.
Creatures you control have trample. (Each of those creatures can deal excess combat damage to the player or planeswalker it's attacking.)
Whenever a creature you control with power 4 or greater enters, draw a card.

Vesuvan Drifter

Flying
You may look at the top card of your library any time.
At the beginning of each combat, you may reveal the top card of your library. If you reveal a creature card this way, this creature becomes a copy of that card until end of turn, except it has flying.

Omen Hawker

{T}: Add {C}{U}. Spend this mana only to activate abilities.

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.

Shower of Arrows

Destroy target artifact, enchantment, or creature with flying. Scry 1.

Genesis Wave

Reveal the top X cards of your library. You may put any number of permanent cards with mana value X or less from among them onto the battlefield. Then put all cards revealed this way that weren't put onto the battlefield into your graveyard.

Dragon Wings

Enchant creature
Enchanted creature has flying.
Cycling {1}{U} ({1}{U}, Discard this card: Draw a card.)
When a creature with mana value 6 or greater enters, you may return this card from your graveyard to the battlefield attached to that creature.

Worldly Tutor

Search your library for a creature card, reveal it, then shuffle and put the card on top.

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.

Kinnan, Bonder Prodigy

Whenever you tap a nonland permanent for mana, add one mana of any type that permanent produced.
{5}{G}{U}: Look at the top five cards of your library. You may put a non-Human creature card from among them onto the battlefield. Put the rest on the bottom of your library in a random order.

Nature's Lore

Search your library for a Forest card, put that card onto the battlefield, then shuffle.

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."

Tropical Island

Castle Garenbrig

This land enters tapped unless you control a Forest.
{T}: Add {G}.
{2}{G}{G}, {T}: Add six {G}. Spend this mana only to cast creature spells or activate abilities of creatures.

Wormhole Serpent

{3}{U}: Target creature can't be blocked this turn.

Serpent of Yawning Depths

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

Quest for Ancient Secrets

Whenever a card is put into your graveyard from anywhere, you may put a quest counter on this enchantment.
Remove five quest counters from this enchantment and sacrifice it: Target player shuffles their graveyard into their library.

Joint Exploration

Kicker {G} (You may pay an additional {G} as you cast this spell.)
Scry 2, then draw a card. If this spell was kicked, you may put a land card from your hand onto the battlefield.

Castle Vantress

This land enters tapped unless you control an Island.
{T}: Add {U}.
{2}{U}{U}, {T}: Scry 2.

Koma, World-Eater

This spell can't be countered.
Trample, ward {4}
Whenever Koma deals combat damage to a player, create four 3/3 blue Serpent creature tokens named Koma's Coil.

Cream of the Crop

Whenever a creature you control enters, you may look at the top X cards of your library, where X is that creature's power. If you do, put one of those cards on top of your library and the rest on the bottom of your library in any order.

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.

Shipbreaker Kraken

{6}{U}{U}: Monstrosity 4. (If this creature isn't monstrous, put four +1/+1 counters on it and it becomes monstrous.)
When this creature becomes monstrous, tap up to four target creatures. Those creatures don't untap during their controllers' untap steps for as long as you control this creature.

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}.

Arixmethes, Slumbering Isle

Arixmethes enters 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}.

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.

Skyshroud Claim

Search your library for up to two Forest cards, put them onto the battlefield, then shuffle.

Breeding Pool

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

Scroll Rack

{1}, {T}: Exile any number of cards from your hand face down. Put that many cards from the top of your library into your hand. Then look at the exiled cards and put them on top of your library in any order.

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.

Ponder

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

Kenessos, Priest of Thassa

If you would scry a number of cards, scry that many cards plus one instead.
{3}{G/U}: Look at the top card of your library. If it's a Kraken, Leviathan, Octopus, or Serpent creature card, you may put it onto the battlefield. If you don't put the card onto the battlefield, you may put it on the bottom of your library.

Colossal Majesty

At the beginning of your upkeep, if you control a creature with power 4 or greater, draw a card.

Cryptic Command

Choose two —
• Counter target spell.
• Return target permanent to its owner's hand.
• Tap all creatures your opponents control.
• Draw a card.

Rogue's Passage

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

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.

Bugenhagen, Wise Elder

Reach
At the beginning of your upkeep, if you control a creature with power 7 or greater, draw a card.
{T}: Add one mana of any color.

Kiora, Sovereign of the Deep

Vigilance, ward {3}
Whenever you cast a Kraken, Leviathan, Octopus, or Serpent spell from your hand, look at the top X cards of your library, where X is that spell's mana value. You may cast a spell with mana value less than X from among them without paying its mana cost. Put the rest on the bottom of your library in a random order.

Aesi, Tyrant of Gyre Strait

You may play an additional land on each of your turns.
Landfall — Whenever a land you control enters, you may draw a card.

Tangled Islet

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

Mikokoro, Center of the Sea

{T}: Add {C}.
{2}, {T}: Each player draws a card.

Snow-Covered Forest

Preordain

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.)

Fanatic of Rhonas

{T}: Add {G}.
Ferocious — {T}: Add {G}{G}{G}{G}. Activate only if you control a creature with power 4 or greater.
Eternalize {2}{G}{G} ({2}{G}{G}, Exile this card from your graveyard: Create a token that's a copy of it, except it's a 4/4 black Zombie Snake Druid with no mana cost. Eternalize only as a sorcery.)

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.

Simic Sky Swallower

Flying, trample
Shroud (This creature can't be the target of spells or abilities.)

Maraleaf Pixie

Fated Infatuation

Create a token that's a copy of target creature you control. If it's your turn, scry 2.

Snow-Covered Island

Kiora, Behemoth Beckoner

Whenever a creature you control with power 4 or greater enters, draw a card.
−1: Untap target permanent.

Gilanra, Caller of Wirewood

{T}: Add {G}. When you spend this mana to cast a spell with mana value 6 or greater, draw a card.
Partner (You can have two commanders if both have partner.)

Smuggler's Surprise

Spree (Choose one or more additional costs.)
+ {2} — Mill four cards. You may put up to two creature and/or land cards from among the milled cards into your hand.
+ {4}{G} — You may put up to two creature cards from your hand onto the battlefield.
+ {1} — Creatures you control with power 4 or greater gain hexproof and indestructible until end of turn.

Track Down

Scry 3, then reveal the top card of your library. If it's a creature or land card, draw a card. (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.)

Quandrix Campus

This land enters tapped.
{T}: Add {G} or {U}.
{4}, {T}: Scry 1.

Biomancer's Familiar

Activated abilities of creatures you control cost {2} less to activate. This effect can't reduce the mana in that cost to less than one mana.
{T}: The next time target creature adapts this turn, it adapts as though it had no +1/+1 counters on it.

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.)

Mosswort Bridge

Hideaway 4 (When this land enters, look at the top four cards of your library, exile one face down, then put the rest on the bottom in a random order.)
This land enters tapped.
{T}: Add {G}.
{G}, {T}: You may play the exiled card without paying its mana cost if creatures you control have total power 10 or greater.

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.

Mystic Speculation

Buyback {2} (You may pay an additional {2} as you cast this spell. If you do, put this card into your hand as it resolves.)
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.)

Krosan Drover

Creature spells you cast with mana value 6 or greater cost {2} less to cast.

The Great Henge

This spell costs {X} less to cast, where X is the greatest power among creatures you control.
{T}: Add {G}{G}. You gain 2 life.
Whenever a nontoken creature you control enters, put a +1/+1 counter on it and draw a card.

Koma, Cosmos Serpent

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 gains indestructible until end of turn.

Day's Undoing

Each player shuffles their hand and graveyard into their library, then draws seven cards. If it's your turn, end the turn. (Exile all spells and abilities from the stack, including this card. Discard down to your maximum hand size. Damage wears off, and "this turn" and "until end of turn" effects end.)

Monstrosity of the Lake

When Monstrosity of the Lake enters, 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.)

Soothsaying

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

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.

Misty Rainforest

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

Rivendell

Rivendell enters tapped unless you control a legendary creature.
{T}: Add {U}.
{1}{U}, {T}: Scry 2. Activate only if you control a legendary creature.

Brainstorm

Draw three cards, then put two cards from your hand on top of your library in any order.

Vineglimmer Snarl

As this land enters, you may reveal a Forest or Island card from your hand. If you don't, this land enters tapped.
{T}: Add {G} or {U}.

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.

Brinelin, the Moon Kraken

When Brinelin enters and whenever you cast a spell with mana value 6 or greater, you may return target nonland permanent to its owner's hand.
Partner (You can have two commanders if both have partner.)

Three Visits

Search your library for a Forest card, put it onto the battlefield, then shuffle.

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.)

Voidslime

Counter target spell, activated ability, or triggered ability. (Mana abilities can't be targeted.)