Eyes of Gitaxias

Incubate 3. (Create an Incubator token with three +1/+1 counters on it and "{2}: Transform this artifact." It transforms into a 0/0 Phyrexian artifact creature.)
Draw a card.

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.

Cartouche of Strength

Enchant creature you control
When Cartouche of Strength enters the battlefield, you may have enchanted creature fight target creature an opponent controls. (Each deals damage equal to its power to the other.)
Enchanted creature gets +1/+1 and has trample.

Opportunity

Flourishing Strike

Choose one —
• Flourishing Strike deals 5 damage to target creature with flying.
• Target creature gets +3/+3 until end of turn.
Entwine {2}{G} (Choose both if you pay the entwine cost.)

Intruder Alarm

Creatures don't untap during their controllers' untap steps.
Whenever a creature enters the battlefield, untap all creatures.

Mana Leak

Counter target spell unless its controller pays {3}.

Hakbal of the Surging Soul

At the beginning of combat on your turn, each Merfolk creature you control 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 the exploring creature, then put the card back or put it into your graveyard.)
Whenever Hakbal of the Surging Soul attacks, you may put a land card from your hand onto the battlefield. If you don't, draw a card.

Contested Game Ball

Whenever you're dealt combat damage, the attacking player gains control of Contested Game Ball and untaps it.
{2}, {T}: Draw a card and put a point counter on Contested Game Ball. Then if it has five or more point counters on it, sacrifice it and create a Treasure token.

Cryptic Serpent

This spell costs {1} less to cast for each instant and sorcery card in your graveyard.

Frilled Sea Serpent

{5}{U}{U}: Frilled Sea Serpent can't be blocked this turn.

Moritte of the Frost

Changeling (This card is every creature type.)
You may have Moritte of the Frost enter the battlefield as a copy of a permanent you control, except it's legendary and snow in addition to its other types and, if it's a creature, it enters with two additional +1/+1 counters on it and has changeling.

Involuntary Cooldown

Tap up to two target artifacts and/or creatures. Put two stun counters on each of them. (If a permanent with a stun counter would become untapped, remove one from it instead.)

Nicanzil, Current Conductor

Whenever a creature you control explores a land card, you may put a land card from your hand onto the battlefield tapped.
Whenever a creature you control explores a nonland card, put a +1/+1 counter on Nicanzil, Current Conductor.

Acquisition Octopus

Whenever Acquisition Octopus or equipped creature deals combat damage to a player, draw a card.
Reconfigure {2} ({2}: Attach to target creature you control; or unattach from a creature. Reconfigure only as a sorcery. While attached, this isn't a creature.)

Guardian Gladewalker

Changeling (This card is every creature type.)
When Guardian Gladewalker enters the battlefield, put a +1/+1 counter on target creature.

Streambed Aquitects

{T}: Target Merfolk creature gets +1/+1 and gains islandwalk until end of turn. (It can't be blocked as long as defending player controls an Island.)
{T}: Target land becomes an Island until end of turn.

Mycoid Maze

(Transforms from Twists and Turns.)
{T}: Add {G}.
{3}{G}, {T}: Look at the top four cards of your library. You may reveal a creature card from among them and put that card into your hand. Put the rest on the bottom of your library in a random order.

Twists and Turns

If a creature you control would explore, instead you scry 1, then that creature explores.
When Twists and Turns enters the battlefield, target creature you control explores.
When a land enters the battlefield under your control, if you control seven or more lands, transform Twists and Turns.

Twists and Turns // Mycoid Maze

Littjara Glade-Warden

Changeling (This card is every creature type.)
{2}{G}, {T}, Exile a creature card from your graveyard: Put two +1/+1 counters on target creature. Activate only as a sorcery.

Seeker of Sunlight

{2}{G}: Seeker of Sunlight explores. Activate only as a sorcery. (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.)

River Herald Guide

Vigilance
When River Herald Guide 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.)

Kraken Hatchling

Hidden Cataract

Hidden Cataract enters the battlefield tapped.
{T}: Add {U}.
{4}{U}, {T}, Sacrifice Hidden Cataract: Discover 4. Activate only as a sorcery. (Exile cards from the top of your library until you exile a nonland card with mana value 4 or less. Cast it without paying its mana cost or put it into your hand. Put the rest on the bottom in a random order.)

Skyclave Invader

Flying
When this creature transforms into Skyclave Invader, look at the top card of your library. If it's a land card, you may put it onto the battlefield. If you don't put the card onto the battlefield, put it into your hand.

Skyclave Aerialist

Flying
{4}{G/P}: Transform Skyclave Aerialist. Activate only as a sorcery. ({G/P} can be paid with either {G} or 2 life.)

Skyclave Aerialist // Skyclave Invader

Hidden Nursery

Hidden Nursery enters the battlefield tapped.
{T}: Add {G}.
{4}{G}, {T}, Sacrifice Hidden Nursery: Discover 4. Activate only as a sorcery. (Exile cards from the top of your library until you exile a nonland card with mana value 4 or less. Cast it without paying its mana cost or put it into your hand. Put the rest on the bottom in a random order.)

Scourge of Fleets

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.

Kraken of the Straits

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

Assimilate Essence

Counter target creature or battle spell unless its controller pays {4}. If they do, you incubate 2. (Create an Incubator token with two +1/+1 counters on it and "{2}: Transform this artifact." It transforms into a 0/0 Phyrexian artifact creature.)

Impulse

Look at the top four cards of your library. Put one of them into your hand and the rest on the bottom of your library in any order.

Cenote Scout

When Cenote 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.)

Over the Edge

Choose one —
• Destroy target artifact or enchantment.
• Target creature you control explores, then it explores again. (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 that creature, then put the card back or put it into your graveyard. Then repeat this process.)

Commune with Nature

Look at the top five cards of your library. You may reveal a creature card from among them and put it into your hand. Put the rest on the bottom of your library in any order.

Explorer's Cache

Explorer's Cache enters the battlefield with two +1/+1 counters on it.
Whenever a creature you control with a +1/+1 counter on it dies, put a +1/+1 counter on Explorer's Cache.
{T}: Move a +1/+1 counter from Explorer's Cache onto target creature. Activate only as a sorcery.

Undercity Upheaval

Undergrowth — Distribute X +1/+1 counters among any number of target creatures you control, where X is the number of creature cards in your graveyard as you cast this spell. Creatures you control gain vigilance until end of turn.

River Herald Scout

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.)

Temporal Cleansing

Convoke (Your creatures can help cast this spell. Each creature you tap while casting this spell pays for {1} or one mana of that creature's color.)
The owner of target nonland permanent puts it into their library second from the top or on the bottom.

Moment of Truth

Look at the top three cards of your library. Put one of those cards into your hand, one into your graveyard, and one on the bottom of your library.

Solve the Equation

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

Rooftop Nuisance

Casualty 1 (As you cast this spell, you may sacrifice a creature with power 1 or greater. When you do, copy this spell and you may choose a new target for the copy.)
Tap target creature. It doesn't untap during its controller's next untap step.
Draw a card.

Turnabout

Choose artifact, creature, or land. Tap all untapped permanents of the chosen type target player controls, or untap all tapped permanents of that type that player controls.

Waterwind Scout

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.")

Tolarian Terror

This spell costs {1} less to cast for each instant and sorcery card in your graveyard.
Ward {2} (Whenever this creature becomes the target of a spell or ability an opponent controls, counter it unless that player pays {2}.)

Orazca Puzzle-Door

{1}, {T}, Sacrifice Orazca Puzzle-Door: Look at the top two cards of your library. Put one of those cards into your hand and the other into your graveyard.

Beast Whisperer

Whenever you cast a creature spell, draw a card.

Aquitect's Will

Put a flood counter on target land. That land is an Island in addition to its other types for as long as it has a flood counter on it. If you control a Merfolk, draw a card.

Malamet Battle Glyph

Choose target creature you control and target creature you don't control. If the creature you control entered the battlefield this turn, put a +1/+1 counter on it. Then those creatures fight each other.

Island

Sky Diamond

Sky Diamond enters the battlefield tapped.
{T}: Add {U}.

Staggering Size

Target creature gets +3/+3 and gains trample until end of turn.

Giant Growth

Target creature gets +3/+3 until end of turn.

Soothsayer Adept

{1}{U}, {T}: Draw a card, then discard a card.

Curiosity

Enchant creature
Whenever enchanted creature deals damage to an opponent, you may draw a card.

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.

Steelclad Serpent

Steelclad Serpent can't attack unless you control another artifact.

Sunbird Effigy

Flying, vigilance, haste
Sunbird Effigy's power and toughness are each equal to the number of colors among the exiled cards used to craft it.
{T}: For each color among the exiled cards used to craft Sunbird Effigy, add one mana of that color.

Sunbird Standard

{T}: Add one mana of any color.
Craft with one or more {5} ({5}, Exile this artifact, Exile one or more other permanents you control and/or cards from your graveyard: Return this card transformed under its owner's control. Craft only as a sorcery.)

Sunbird Standard // Sunbird Effigy

Scroll Thief

Whenever Scroll Thief deals combat damage to a player, draw a card.

In the Presence of Ages

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.

Walk with the Ancestors

Return up to one target permanent card from your graveyard to your hand. Discover 4. (Exile cards from the top of your library until you exile a nonland card with mana value 4 or less. Cast it without paying its mana cost or put it into your hand. Put the rest on the bottom in a random order.)

Up the Beanstalk

When Up the Beanstalk enters the battlefield and whenever you cast a spell with mana value 5 or greater, draw a card.

Essence Scatter

Biblioplex Kraken

When Biblioplex Kraken enters the battlefield, scry 3. (Look at the top three cards of your library, then put any number of them on the bottom of your library and the rest on top in any order.)
Whenever Biblioplex Kraken attacks, you may return another creature you control to its owner's hand. If you do, Biblioplex Kraken can't be blocked this turn.

Xolatoyac, the Smiling Flood

Whenever Xolatoyac, the Smiling Flood enters the battlefield or attacks, put a flood counter on target land. That land is an Island in addition to its other types for as long as it has a flood counter on it.
At the beginning of your end step, untap each permanent you control with a counter on it.

Hunter's Blowgun

Equipped creature gets +1/+1.
Equipped creature has deathtouch as long as it's your turn. Otherwise, it has reach.
Equip {2} ({2}: Attach to target creature you control. Equip only as a sorcery.)

Runaway Boulder

Flash
When Runaway Boulder enters the battlefield, it deals 6 damage to target creature an opponent controls.
Cycling {2} ({2}, Discard this card: Draw a card.)

Forest

Uncharted Haven

Uncharted Haven enters the battlefield tapped.
As Uncharted Haven enters the battlefield, choose a color.
{T}: Add one mana of the chosen color.

Thornwood Falls

Thornwood Falls enters the battlefield tapped.
When Thornwood Falls enters the battlefield, you gain 1 life.
{T}: Add {G} or {U}.

Buried Treasure

{T}, Sacrifice Buried Treasure: Add one mana of any color.
{5}, Exile Buried Treasure from your graveyard: Discover 5. Activate only as a sorcery. (Exile cards from the top of your library until you exile a nonland card with mana value 5 or less. Cast it without paying its mana cost or put it into your hand. Put the rest on the bottom in a random order.)

Cumber Stone

Creatures your opponents control get -1/-0.

Triton Shorethief

Reservoir Kraken

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."