Drowner Initiate

Whenever a player casts a blue spell, you may pay {1}. If you do, target player mills two cards.

Double Major

Copy target creature spell you control, except it isn't legendary if the spell is legendary. (A copy of a creature spell becomes a token.)

Cold-Eyed Selkie

Islandwalk (This creature can't be blocked as long as defending player controls an Island.)
Whenever this creature deals combat damage to a player, you may draw that many cards.

Eutropia the Twice-Favored

Constellation — Whenever an enchantment you control enters, put a +1/+1 counter on target creature. That creature gains flying until end of turn.

Awesome Presence

Enchant creature
Enchanted creature can't be blocked unless defending player pays {3} for each creature they control that's blocking it.

Moonring Island

({T}: Add {U}.)
This land enters tapped.
{U}, {T}: Look at the top card of target player's library. Activate only if you control two or more blue permanents.

Forerunner of the Heralds

When this creature enters, you may search your library for a Merfolk card, reveal it, then shuffle and put that card on top.
Whenever another Merfolk you control enters, put a +1/+1 counter on this creature.

Darting Merfolk

{U}: Return this creature to its owner's hand.

Deeproot Elite

Whenever another Merfolk you control enters, put a +1/+1 counter on target Merfolk you control.

Clone Legion

For each creature target player controls, create a token that's a copy of that creature.

Merfolk Mistbinder

Coralhelm Commander

Level up {1} ({1}: Put a level counter on this. Level up only as a sorcery.)
LEVEL 2-3
3/3
Flying
LEVEL 4+
4/4
Flying
Other Merfolk creatures you control get +1/+1.

Coral Fighters

Whenever this creature attacks and isn't blocked, look at the top card of defending player's library. You may put that card on the bottom of that player's library.

Forest

Bounty of the Luxa

At the beginning of your first main phase, remove all flood counters from this enchantment. If no counters were removed this way, put a flood counter on this enchantment and draw a card. Otherwise, add {C}{G}{U}.

Coral Commando

Abundant Growth

Enchant land
When this Aura enters, draw a card.
Enchanted land has "{T}: Add one mana of any color."

Asceticism

Creatures you control have hexproof.
{1}{G}: Regenerate target creature. (The next time it would be destroyed this turn, instead tap it, remove it from combat, and heal all damage on it.)

Deepchannel Mentor

Blue creatures you control can't be blocked.

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.

Cascade Seer

When this creature enters, scry X, where X is the number of creatures in your party. (Your party consists of up to one each of Cleric, Rogue, Warrior, and Wizard.)

Deepwater Hypnotist

Inspired — Whenever this creature becomes untapped, target creature an opponent controls gets -3/-0 until end of turn.

Oran-Rief, the Vastwood

This land enters tapped.
{T}: Add {G}.
{T}: Put a +1/+1 counter on each green creature that entered this turn.

Twincast

Copy target instant or sorcery spell. You may choose new targets for the copy.

Blockade Runner

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

Cleric of Chill Depths

Whenever this creature blocks a creature, that creature doesn't untap during its controller's next untap step.

Doubling Season

If an effect would create one or more tokens under your control, it creates twice that many of those tokens instead.
If an effect would put one or more counters on a permanent you control, it puts twice that many of those counters on that permanent instead.

Rite of Replication

Kicker {5} (You may pay an additional {5} as you cast this spell.)
Create a token that's a copy of target creature. If this spell was kicked, create five of those tokens instead.

Parallel Lives

If an effect would create one or more tokens under your control, it creates twice that many of those tokens instead.

Kalonian Twingrove

Kalonian Twingrove's power and toughness are each equal to the number of Forests you control.
When this creature enters, create a green Treefolk Warrior creature token with "This token's power and toughness are each equal to the number of Forests you control."

Deeproot Champion

Whenever you cast a noncreature spell, put a +1/+1 counter on this creature.

Doubling Cube

{3}, {T}: Double the amount of each type of unspent mana you have.

Burgeoning

Whenever an opponent plays a land, you may put a land card from your hand onto the battlefield.

Spelltwine

Exile target instant or sorcery card from your graveyard and target instant or sorcery card from an opponent's graveyard. Copy those cards. Cast the copies if able without paying their mana costs. Exile Spelltwine.

Helm of the Host

At the beginning of combat on your turn, create a token that's a copy of equipped creature, except the token isn't legendary. That token gains haste.
Equip {5}

Cursecatcher

Sacrifice this creature: Counter target instant or sorcery spell unless its controller pays {1}.

Island

Mirror Match

Cast this spell only during the declare blockers step.
For each creature attacking you or a planeswalker you control, create a token that's a copy of that creature and that's blocking that creature. Exile those tokens at end of combat.

Kumena's Speaker

This creature gets +1/+1 as long as you control another Merfolk or an Island.

Spark Double

You may have this creature enter as a copy of a creature or planeswalker you control, except it enters with an additional +1/+1 counter on it if it's a creature, it enters with an additional loyalty counter on it if it's a planeswalker, and it isn't legendary.

Fallowsage

Whenever this creature becomes tapped, you may draw a card.

Desolation Twin

When you cast this spell, create a 10/10 colorless Eldrazi creature token.

Gaea's Skyfolk

Copy Artifact

You may have this enchantment enter as a copy of any artifact on the battlefield, except it's an enchantment in addition to its other types.

Tropical Island

Jungleborn Pioneer

When this creature enters, create a 1/1 blue Merfolk creature token with hexproof. (It can't be the target of spells or abilities your opponents control.)

Jade Bearer

When this creature enters, put a +1/+1 counter on another target Merfolk you control.

Think Twice

Draw a card.
Flashback {2}{U} (You may cast this card from your graveyard for its flashback cost. Then exile it.)

Stunt Double

Flash
You may have this creature enter as a copy of any creature on the battlefield.

Brineborn Cutthroat

Flash (You may cast this spell any time you could cast an instant.)
Whenever you cast a spell during an opponent's turn, put a +1/+1 counter on this creature.

Enclave Elite

Multikicker {1}{U} (You may pay an additional {1}{U} any number of times as you cast this spell.)
Islandwalk (This creature can't be blocked as long as defending player controls an Island.)
This creature enters with a +1/+1 counter on it for each time it was kicked.

Primal Vigor

If one or more tokens would be created, twice that many of those tokens are created instead.
If one or more +1/+1 counters would be put on a creature, twice that many +1/+1 counters are put on that creature instead.

Body Double

You may have this creature enter as a copy of any creature card in a graveyard.

Alchemist's Refuge

{T}: Add {C}.
{G}{U}, {T}: You may cast spells this turn as though they had flash.

Glintwing Invoker

{7}{U}: This creature gets +3/+3 and gains flying until end of turn.

Drowner of Secrets

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

Aquatic Incursion

When this enchantment enters, create two 1/1 blue Merfolk creature tokens with hexproof. (They can't be the targets of spells or abilities your opponents control.)
{3}{U}: Target Merfolk can't be blocked this turn.

Copy Enchantment

You may have this enchantment enter as a copy of any enchantment on the battlefield.

Combine Guildmage

{1}{G}, {T}: This turn, each creature you control enters with an additional +1/+1 counter on it.
{1}{U}, {T}: Move a +1/+1 counter from target creature you control onto another target creature you control.

Sapseep Forest

({T}: Add {G}.)
This land enters tapped.
{G}, {T}: You gain 1 life. Activate only if you control two or more green permanents.

Adrix and Nev, Twincasters

Ward {2} (Whenever this creature becomes the target of a spell or ability an opponent controls, counter it unless that player pays {2}.)
If one or more tokens would be created under your control, twice that many of those tokens are created instead.

Spellweaver Duo

Assist (Another player can pay up to {6} of this spell's cost.)
When this creature enters, you may return target tapped creature to its owner's hand.

Clone

You may have this creature enter as a copy of any creature on the battlefield.

Lord of Atlantis

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

Coralhelm Guide

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

Ghastbark Twins

Trample (This creature can deal excess combat damage to the player or planeswalker it's attacking.)
This creature can block an additional creature each combat.

Merfolk of the Depths

Flash (You may cast this spell any time you could cast an instant.)

Twinning Staff

If you would copy a spell one or more times, instead copy it that many times plus an additional time. You may choose new targets for the additional copy.
{7}, {T}: Copy target instant or sorcery spell you control. You may choose new targets for the copy.

Academy Ruins

{T}: Add {C}.
{1}{U}, {T}: Put target artifact card from your graveyard on top of your library.

Dakra Mystic

{U}, {T}: Each player reveals the top card of their library. You may put the revealed cards into their owners' graveyards. If you don't, each player draws a card.

Mirrorworks

Whenever another nontoken artifact you control enters, you may pay {2}. If you do, create a token that's a copy of that artifact.