Pollen Lullaby

Prevent all combat damage that would be dealt this turn. Clash with an opponent. If you win, creatures that player controls don't untap during the player's next untap step. (Each clashing player reveals the top card of their library, then puts that card on the top or bottom. A player wins if their card had a higher mana value.)

Sygg, River Guide

Islandwalk (This creature can't be blocked as long as defending player controls an Island.)
{1}{W}: Target Merfolk you control gains protection from the color of your choice until end of turn.

Austere Command

Choose two —
• Destroy all artifacts.
• Destroy all enchantments.
• Destroy all creatures with mana value 3 or less.
• Destroy all creatures with mana value 4 or greater.

Goldmeadow Harrier

Temple of Enlightenment

Temple of Enlightenment enters tapped.
When Temple of Enlightenment enters, scry 1.
{T}: Add {W} or {U}.

Crib Swap

Changeling (This card is every creature type.)
Exile target creature. Its controller creates a 1/1 colorless Shapeshifter creature token with changeling.

Vivid Meadow

Vivid Meadow enters tapped with two charge counters on it.
{T}: Add {W}.
{T}, Remove a charge counter from Vivid Meadow: Add one mana of any color.

Galepowder Mage

Flying
Whenever Galepowder Mage attacks, exile another target creature. Return that card to the battlefield under its owner's control at the beginning of the next end step.

Purity

Flying
If noncombat damage would be dealt to you, prevent that damage. You gain life equal to the damage prevented this way.
When Purity is put into a graveyard from anywhere, shuffle it into its owner's library.

Wanderwine Hub

As Wanderwine Hub enters, you may reveal a Merfolk card from your hand. If you don't, Wanderwine Hub enters tapped.
{T}: Add {W} or {U}.

Command Tower

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

Faerie Trickery

Counter target non-Faerie spell. If that spell is countered this way, exile it instead of putting it into its owner's graveyard.

Inkfathom Divers

Islandwalk (This creature can't be blocked as long as defending player controls an Island.)
When Inkfathom Divers enters, look at the top four cards of your library, then put them back in any order.

Benthicore

When Benthicore enters, create two 1/1 blue Merfolk Wizard creature tokens.
Tap two untapped Merfolk you control: Untap Benthicore. It gains shroud until end of turn. (It can't be the target of spells or abilities.)

Vivid Creek

Vivid Creek enters tapped with two charge counters on it.
{T}: Add {U}.
{T}, Remove a charge counter from Vivid Creek: Add one mana of any color.

Spellstutter Sprite

Flash
Flying
When Spellstutter Sprite enters, counter target spell with mana value X or less, where X is the number of Faeries you control.

Aethersnipe

When Aethersnipe enters, return target nonland permanent to its owner's hand.
Evoke {1}{U}{U} (You may cast this spell for its evoke cost. If you do, it's sacrificed when it enters.)

Mirror Entity

Changeling (This card is every creature type.)
{X}: Until end of turn, creatures you control have base power and toughness X/X and gain all creature types.

Flooded Strand

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

Militia's Pride

Whenever a nontoken creature you control attacks, you may pay {W}. If you do, create a 1/1 white Kithkin Soldier creature token that's tapped and attacking.

Wanderwine Prophets

Champion a Merfolk (When this enters, sacrifice it unless you exile another Merfolk you control. When this leaves the battlefield, that card returns to the battlefield.)
Whenever Wanderwine Prophets deals combat damage to a player, you may sacrifice a Merfolk. If you do, take an extra turn after this one.

Amoeboid Changeling

Changeling (This card is every creature type.)
{T}: Target creature gains all creature types until end of turn.
{T}: Target creature loses all creature types until end of turn.

Hoofprints of the Stag

Whenever you draw a card, you may put a hoofprint counter on Hoofprints of the Stag.
{2}{W}, Remove four hoofprint counters from Hoofprints of the Stag: Create a 4/4 white Elemental creature token with flying. Activate only during your turn.

Midnight Clock

{T}: Add {U}.
{2}{U}: Put an hour counter on Midnight Clock.
At the beginning of each upkeep, put an hour counter on Midnight Clock.
When the twelfth hour counter is put on Midnight Clock, shuffle your hand and graveyard into your library, then draw seven cards. Exile Midnight Clock.

Windbrisk Heights

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.)
Windbrisk Heights enters tapped.
{T}: Add {W}.
{W}, {T}: You may play the exiled card without paying its mana cost if you attacked with three or more creatures this turn.

Veteran of the Depths

Whenever Veteran of the Depths becomes tapped, you may put a +1/+1 counter on it.

Merfolk Sovereign

Other Merfolk creatures you control get +1/+1.
{T}: Target Merfolk creature can't be blocked this turn.

Port Town

As Port Town enters, you may reveal a Plains or Island card from your hand. If you don't, Port Town enters tapped.
{T}: Add {W} or {U}.

Ajani Goldmane

+1: You gain 2 life.
−1: Put a +1/+1 counter on each creature you control. Those creatures gain vigilance until end of turn.
−6: Create a white Avatar creature token. It has "This creature's power and toughness are each equal to your life total."

Kindred Discovery

As Kindred Discovery enters, choose a creature type.
Whenever a creature you control of the chosen type enters or attacks, draw a card.

Deeptread Merrow

{U}: Deeptread Merrow gains islandwalk until end of turn. (It can't be blocked as long as defending player controls an Island.)

Judge of Currents

Whenever a Merfolk you control becomes tapped, you may gain 1 life.

Hallowed Fountain

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

Shimmering Grotto

{T}: Add {C}.
{1}, {T}: Add one mana of any color.

Shapesharer

Changeling (This card is every creature type.)
{2}{U}: Target Shapeshifter becomes a copy of target creature until your next turn.

Prairie Stream

({T}: Add {W} or {U}.)
Prairie Stream enters tapped unless you control two or more basic lands.

Guile

Guile can't be blocked except by three or more creatures.
If a spell or ability you control would counter a spell, instead exile that spell and you may play that card without paying its mana cost.
When Guile is put into a graveyard from anywhere, shuffle it into its owner's library.

Azorius Signet

Shields of Velis Vel

Changeling (This card is every creature type.)
Creatures target player controls get +0/+1 and gain all creature types until end of turn.

Fallowsage

Whenever Fallowsage becomes tapped, you may draw a card.

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.)

Captivating Glance

Enchant creature
At the beginning of your end step, clash with an opponent. If you win, gain control of enchanted creature. Otherwise, that player gains control of enchanted creature. (Each clashing player reveals the top card of their library, then puts that card on the top or bottom. A player wins if their card had a higher mana value.)

Familiar's Ruse

As an additional cost to cast this spell, return a creature you control to its owner's hand.
Counter target spell.

Sword of the Animist

Equipped creature gets +1/+1.
Whenever equipped creature attacks, you may search your library for a basic land card, put it onto the battlefield tapped, then shuffle.
Equip {2}

Whirlpool Whelm

Clash with an opponent, then return target creature to its owner's hand. If you win, you may put that creature on top of its owner's library instead. (Each clashing player reveals the top card of their library, then puts that card on the top or bottom. A player wins if their card had a higher mana value.)

Lord of Atlantis

Other Merfolk get +1/+1 and have islandwalk. (They can't be blocked as long as defending player controls an Island.)

Commander's Sphere

{T}: Add one mana of any color in your commander's color identity.
Sacrifice Commander's Sphere: Draw a card.

Arcane Signet

Silvergill Douser

{T}: Target creature gets -X/-0 until end of turn, where X is the number of Merfolk and/or Faeries you control.

Tideshaper Mystic

{T}: Target land becomes the basic land type of your choice until end of turn. Activate only during your turn.

Herbal Poultice

{3}, Sacrifice Herbal Poultice: Regenerate target creature.

Dolmen Gate

Prevent all combat damage that would be dealt to attacking creatures you control.

Springleaf Drum

{T}, Tap an untapped creature you control: Add one mana of any color.

Door of Destinies

As Door of Destinies enters, choose a creature type.
Whenever you cast a spell of the chosen type, put a charge counter on Door of Destinies.
Creatures you control of the chosen type get +1/+1 for each charge counter on Door of Destinies.

Zephyr Net

Enchant creature
Enchanted creature has defender and flying.

Harpoon Sniper

{W}, {T}: Harpoon Sniper deals X damage to target attacking or blocking creature, where X is the number of Merfolk you control.

Glacial Fortress

Glacial Fortress enters tapped unless you control a Plains or an Island.
{T}: Add {W} or {U}.

Esper Panorama

{T}: Add {C}.
{1}, {T}, Sacrifice Esper Panorama: Search your library for a basic Plains, Island, or Swamp card, put it onto the battlefield tapped, then shuffle.

Wanderer's Twig

{1}, Sacrifice Wanderer's Twig: Search your library for a basic land card, reveal it, put it into your hand, then shuffle.

Irrigated Farmland

({T}: Add {W} or {U}.)
Irrigated Farmland enters tapped.
Cycling {2} ({2}, Discard this card: Draw a card.)

Moonglove Extract

Sacrifice Moonglove Extract: It deals 2 damage to any target.

Cloudgoat Ranger

When Cloudgoat Ranger enters, create three 1/1 white Kithkin Soldier creature tokens.
Tap three untapped Kithkin you control: Cloudgoat Ranger gets +2/+0 and gains flying until end of turn.

Island

Ponder

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

Vanquisher's Banner

As Vanquisher's Banner enters, choose a creature type.
Creatures you control of the chosen type get +1/+1.
Whenever you cast a creature spell of the chosen type, draw a card.

Plains

Runed Stalactite

Equipped creature gets +1/+1 and is every creature type.
Equip {2}

Deeproot Waters

Whenever you cast a Merfolk spell, create a 1/1 blue Merfolk creature token with hexproof. (A creature with hexproof can't be the target of spells or abilities your opponents control.)

Glimmerdust Nap

Enchant tapped creature
Enchanted creature doesn't untap during its controller's untap step.

Forced Fruition

Whenever an opponent casts a spell, that player draws seven cards.

Azorius Chancery

Azorius Chancery enters tapped.
When Azorius Chancery enters, return a land you control to its owner's hand.
{T}: Add {W}{U}.

Wellgabber Apothecary

{1}{W}: Prevent all damage that would be dealt to target tapped Merfolk or Kithkin creature this turn.

Mystic Gate

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

Sower of Temptation

Flying
When Sower of Temptation enters, gain control of target creature for as long as Sower of Temptation remains on the battlefield.

Paperfin Rascal

When Paperfin Rascal enters, clash with an opponent. If you win, put a +1/+1 counter on Paperfin Rascal. (Each clashing player reveals the top card of their library, then puts that card on the top or bottom. A player wins if their card had a higher mana value.)

Drowner of Secrets

Tap an untapped Merfolk you control: Target player mills a card.

Summon the School

Create two 1/1 blue Merfolk Wizard creature tokens.
Tap four untapped Merfolk you control: Return Summon the School from your graveyard to your hand.

Merrow Reejerey

Other Merfolk creatures you control get +1/+1.
Whenever you cast a Merfolk spell, you may tap or untap target permanent.

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.

Merrow Commerce

At the beginning of your end step, untap all Merfolk you control.

Surgespanner

Whenever Surgespanner becomes tapped, you may pay {1}{U}. If you do, return target permanent to its owner's hand.

Wispmare

Flying
When Wispmare enters, destroy target enchantment.
Evoke {W} (You may cast this spell for its evoke cost. If you do, it's sacrificed when it enters.)

Wings of Velis Vel

Changeling (This card is every creature type.)
Until end of turn, target creature has base power and toughness 4/4, gains all creature types, and gains flying.

Master of the Pearl Trident

Other Merfolk creatures you control get +1/+1 and have islandwalk. (They can't be blocked as long as defending player controls an Island.)

Path of Ancestry

Path of Ancestry enters tapped.
{T}: Add one mana of any color in your commander's color identity. When that mana is spent to cast a creature spell that shares a creature type with your commander, scry 1. (Look at the top card of your library. You may put that card on the bottom.)

Sea of Clouds

Sea of Clouds enters tapped unless you have two or more opponents.
{T}: Add {W} or {U}.

Neck Snap

Destroy target attacking or blocking creature.

Merrow Harbinger

Islandwalk (This creature can't be blocked as long as defending player controls an Island.)
When Merrow Harbinger enters, you may search your library for a Merfolk card, reveal it, then shuffle and put that card on top.

Changeling Hero

Changeling (This card is every creature type.)
Champion a creature (When this enters, sacrifice it unless you exile another creature you control. When this leaves the battlefield, that card returns to the battlefield.)
Lifelink (Damage dealt by this creature also causes you to gain that much life.)

Oblivion Ring

When Oblivion Ring enters, exile another target nonland permanent.
When Oblivion Ring leaves the battlefield, return the exiled card to the battlefield under its owner's control.

Fathom Trawl

Reveal cards from the top of your library until you reveal three nonland cards. Put the nonland cards revealed this way into your hand, then put the rest of the revealed cards on the bottom of your library in any order.

Stonybrook Angler

{1}{U}, {T}: You may tap or untap target creature.

Ego Erasure

Changeling (This card is every creature type.)
Creatures target player controls get -2/-0 and lose all creature types until end of turn.

Jace Beleren

+2: Each player draws a card.
−1: Target player draws a card.
−10: Target player mills twenty cards.

Mulldrifter

Flying
When Mulldrifter enters, draw two cards.
Evoke {2}{U} (You may cast this spell for its evoke cost. If you do, it's sacrificed when it enters.)

Silvergill Adept

As an additional cost to cast this spell, reveal a Merfolk card from your hand or pay {3}.
When Silvergill Adept enters, 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.

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.

Broken Ambitions

Counter target spell unless its controller pays {X}. Clash with an opponent. If you win, that spell's controller mills four cards. (Each clashing player reveals the top card of their library, then puts that card on the top or bottom. A player wins if their card had a higher mana value.)