Ghostly Wings

Enchant creature
Enchanted creature gets +1/+1 and has flying.
Discard a card: Return enchanted creature to its owner's hand.

Faerie Seer

Flying
When this creature enters, 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.)

Cerulean Wisps

Target creature becomes blue until end of turn. Untap that creature.
Draw a card.

Shipwreck Dowser

Prowess (Whenever you cast a noncreature spell, this creature gets +1/+1 until end of turn.)
When this creature enters, return target instant or sorcery card from your graveyard to your hand.

Water Wings

Until end of turn, target creature you control has base power and toughness 4/4 and gains flying and hexproof. (It can't be the target of spells or abilities your opponents control.)

Expanded Anatomy

Put two +1/+1 counters on target creature. It gains vigilance until end of turn.

Leap

Target creature gains flying until end of turn.
Draw a card.

Defy Gravity

Target creature gains flying until end of turn.
Flashback {U} (You may cast this card from your graveyard for its flashback cost. Then exile it.)

Glint

Target creature you control gets +0/+3 and gains hexproof until end of turn. (It can't be the target of spells or abilities your opponents control.)

Mystic Sanctuary

({T}: Add {U}.)
This land enters tapped unless you control three or more other Islands.
When this land enters untapped, you may put target instant or sorcery card from your graveyard on top of your library.

Jeskai Windscout

Flying
Prowess (Whenever you cast a noncreature spell, this creature gets +1/+1 until end of turn.)

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.

Cartouche of Knowledge

Enchant creature you control
When this Aura enters, draw a card.
Enchanted creature gets +1/+1 and has flying.

Hubris

Return target creature and all Auras attached to it to their owners' hands.

Wing Commando

Jhessian Thief

Prowess (Whenever you cast a noncreature spell, this creature gets +1/+1 until end of turn.)
Whenever this creature deals combat damage to a player, draw a card.

Counterspell

Ingenious Skaab

Prowess (Whenever you cast a noncreature spell, this creature gets +1/+1 until end of turn.)
{U}: This creature gets +1/-1 until end of turn.

Crashing Tide

This spell has flash as long as you control a Merfolk.
Return target creature to its owner's hand.
Draw a card.

One With the Wind

Enchant creature
Enchanted creature gets +2/+2 and has flying.

Striped Riverwinder

Hexproof (This creature can't be the target of spells or abilities your opponents control.)
Cycling {U} ({U}, Discard this card: Draw a card.)

Cryptic Serpent

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

Brine Giant

Affinity for enchantments (This spell costs {1} less to cast for each enchantment you control.)

Mistral Singer

Island

Whirlwind Adept

Hexproof (This creature can't be the target of spells or abilities your opponents control.)
Prowess (Whenever you cast a noncreature spell, this creature gets +1/+1 until end of turn.)

Deep-Sea Terror

This creature can't attack unless there are seven or more cards in your graveyard.

Aqueous Form

Enchant creature
Enchanted creature can't be blocked.
Whenever enchanted creature attacks, scry 1. (Look at the top card of your library. You may put that card on the bottom.)

Eel Umbra

Flash (You may cast this spell any time you could cast an instant.)
Enchant creature
Enchanted creature gets +1/+1.
Umbra armor (If enchanted creature would be destroyed, instead remove all damage from it and destroy this Aura.)

Air Marshal

{3}: Target Soldier gains flying until end of turn.

Shaper Apprentice

This creature has flying as long as you control another Merfolk.

Riverwheel Aerialists

Archaeomancer

When this creature enters, return target instant or sorcery card from your graveyard to your hand.

Harbor Serpent

Islandwalk (This creature can't be blocked as long as defending player controls an Island.)
This creature can't attack unless there are five or more Islands on the battlefield.

Viscerid Armor

Enchant creature
Enchanted creature gets +1/+1.
{1}{U}: Return this Aura to its owner's hand.

Stealth Mission

Put two +1/+1 counters on target creature you control. That creature can't be blocked this turn.

Marauding Brinefang

Ward {3} (Whenever this creature becomes the target of a spell or ability an opponent controls, counter it unless that player pays {3}.)
Islandcycling {2} ({2}, Discard this card: Search your library for an Island card, reveal it, put it into your hand, then shuffle.)

Gray Harbor Merfolk

This creature can't be blocked.
This creature gets +2/+0 as long as you control a commander that's a creature or planeswalker.

Negate

Salvager of Secrets

Spectral Flight

Artful Dodge

Target creature can't be blocked this turn.
Flashback {U} (You may cast this card from your graveyard for its flashback cost. Then exile it.)

Stonybrook Angler

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

Merfolk Coralsmith

{1}: This creature gets +1/-1 until end of turn.
When this creature dies, scry 2.

Niblis of Dusk

Skaab Goliath

As an additional cost to cast this spell, exile two creature cards from your graveyard.
Trample

Silvergill Douser

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

Arcane Signet

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

Triton Fortune Hunter

Heroic — Whenever you cast a spell that targets this creature, draw a card.

Arcane Denial

Counter target spell. Its controller may draw up to two cards at the beginning of the next turn's upkeep.
You draw a card at the beginning of the next turn's upkeep.

Saiba Cryptomancer

Flash
Backup 1 (When this creature enters, put a +1/+1 counter on target creature. If that's another creature, it gains the following ability until end of turn.)
Hexproof

Mnemonic Wall

Defender
When this creature enters, you may return target instant or sorcery card from your graveyard to your hand.

Dispel

Capsizing Wave

Return target creature to its owner's hand. (Then exile this card. You may cast the creature later from exile.)

Sword Coast Serpent

This creature can't be blocked as long as you've cast a noncreature spell this turn.

Sword Coast Serpent // Capsizing Wave

Frogify

Enchant creature
Enchanted creature loses all abilities and is a blue Frog creature with base power and toughness 1/1. (It loses all other card types and creature types.)

Dive Down

Starlit Mantle

Flash (You may cast this spell any time you could cast an instant.)
Enchant creature you control
When this Aura enters, enchanted creature gains hexproof until end of turn. (It can't be the target of spells or abilities your opponents control.)
Enchanted creature gets +1/+1.

Goliath Sphinx

Arcane Flight

Enchant creature
Enchanted creature gets +1/+1 and has flying.

High Tide

Until end of turn, whenever a player taps an Island for mana, that player adds an additional {U}.

Stonybrook Banneret

Islandwalk (This creature can't be blocked as long as defending player controls an Island.)
Merfolk spells and Wizard spells you cast cost {1} less to cast.

Cradle of Safety

Flash
Enchant creature you control
When this Aura enters, enchanted creature gains hexproof until end of turn. (It can't be the target of spells or abilities your opponents control.)
Enchanted creature gets +1/+1.

Bubble Up

Put target instant or sorcery card from your graveyard on top of your library. (Then exile this card. You may cast the creature later from exile.)

Aquatic Alchemist

Whenever you cast your first instant or sorcery spell each turn, this creature gets +2/+0 until end of turn.

Aquatic Alchemist // Bubble Up

Fall from Favor

Enchant creature
When this Aura enters, tap enchanted creature and you become the monarch.
Enchanted creature doesn't untap during its controller's untap step unless that player is the monarch.