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.)

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.

Riverwise Augur

When this creature enters, draw three cards, then put two cards from your hand on top of your library in any order.

Windrider Patrol

Flying
Whenever this creature deals combat damage to a player, 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.)

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.)

Aggressive Urge

Target creature gets +1/+1 until end of turn.
Draw a card.

Lord of Atlantis

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

Woodland Stream

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

Coralhelm Guide

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

Merfolk Cave-Diver

Whenever a creature you control explores, this creature gets +1/+0 until end of turn and can't be blocked this turn.

Jadelight Ranger

When this creature enters, it 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 this creature, then put the card back or put it into your graveyard. Then repeat this process.)

World Shaper

Whenever this creature attacks, you may mill three cards.
When this creature dies, return all land cards from your graveyard to the battlefield tapped.

Scroll Thief

Whenever this creature deals combat damage to a player, draw a card.

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.

Talrand, Sky Summoner

Whenever you cast an instant or sorcery spell, create a 2/2 blue Drake creature token with flying.

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.

Storm Sculptor

This creature can't be blocked.
When this creature enters, return a creature you control to its owner's hand.

Saltwater Stalwart

Whenever this creature deals damage to an opponent, target player draws a card.

Library Larcenist

Whenever this creature attacks, draw a card.

River Herald Scout

When this creature enters, 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.)

Merfolk Spy

Islandwalk (This creature can't be blocked as long as defending player controls an Island.)
Whenever this creature deals combat damage to a player, that player reveals a card at random from their hand.

Sure-Footed Infiltrator

Tap another untapped Rogue you control: This creature can't be blocked this turn.
Whenever this creature deals combat damage to a player, draw a card.

Moonlit Scavengers

When this creature enters, if you control an artifact or enchantment, return target creature an opponent controls to its owner's hand.

Bioshift

Move any number of +1/+1 counters from target creature onto another target creature with the same controller.

Deeproot Warrior

Whenever this creature becomes blocked, it gets +1/+1 until end of turn.

Seeker of Sunlight

{2}{G}: This creature 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.)

Naturalize

Cleric of Chill Depths

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

Simic Guildgate

Vodalian Arcanist

{T}: Add {C}. Spend this mana only to cast an instant or sorcery spell.

Giltgrove Stalker

This creature can't be blocked by creatures with power 2 or less.

Salvager of Secrets

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

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.)

Merfolk Coralsmith

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

Expedition Diviner

Flying
As long as you control another Wizard, this creature has "When this creature dies, draw a card."

Merfolk Mistbinder

Umara Skyfalls

Umara Wizard

Whenever you cast an instant, sorcery, or Wizard spell, this creature gains flying until end of turn.

Umara Wizard // Umara Skyfalls

Cenote Scout

Bountiful Harvest

You gain 1 life for each land you control.

Forest

River Herald Guide

Vigilance
When River Herald Guide enters, 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.)

Breeding Pool

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

Seafloor Stalker

{4}{U}: This creature gets +1/+0 until end of turn and can't be blocked this turn. This ability costs {1} less to activate for each creature in your party. (Your party consists of up to one each of Cleric, Rogue, Warrior, and Wizard.)

Merfolk Observer

When this creature enters, look at the top card of target player's library.

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.)

Deeproot Pilgrimage

Whenever one or more nontoken Merfolk you control become tapped, create a 1/1 blue Merfolk creature token with hexproof.

River Heralds' Boon

Put a +1/+1 counter on target creature and a +1/+1 counter on up to one target Merfolk.

Vineshaper Mystic

When this creature enters, put a +1/+1 counter on each of up to two target Merfolk you control.

Coral Merfolk

Triton Shorestalker

Island

Merfolk of the Pearl Trident

Jadecraft Artisan

When this creature enters, target creature gets +2/+2 until end of turn.

Maritime Guard

Simic Locket

{T}: Add {G} or {U}.
{G/U}{G/U}{G/U}{G/U}, {T}, Sacrifice this artifact: Draw two cards.

Nyxborn Triton

Bestow {4}{U} (If you cast this card for its bestow cost, it's an Aura spell with enchant creature. It becomes a creature again if it's not attached to a creature.)
Enchanted creature gets +2/+3.

Tazeem Roilmage

Kicker {4} (You may pay an additional {4} as you cast this spell.)
When this creature enters, if it was kicked, return target instant or sorcery card from your graveyard to your hand.

Coral Commando

Animist's Might

This spell costs {2} less to cast if it targets a legendary creature you control.
Target creature you control deals damage equal to twice its power to target creature or planeswalker you don't control.

Incongruity

Exile target creature. That creature's controller creates a 3/3 green Frog Lizard creature token.

Incubation

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 a random order.

Incubation // Incongruity

Deeproot Champion

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

Waterwind Scout

Flying
When this creature enters, create a Map token. (It's an artifact with "{1}, {T}, Sacrifice this token: Target creature you control explores. Activate only as a sorcery.")

Mist-Cloaked Herald

Titanic Growth

Target creature gets +4/+4 until end of turn.

Wishful Merfolk

Defender
{1}{U}: This creature loses defender and becomes a Human until end of turn.

Hinterland Harbor

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

Thrasios, Triton Hero

{4}: Scry 1, then reveal the top card of your library. If it's a land card, put it onto the battlefield tapped. Otherwise, draw a card.
Partner (You can have two commanders if both have partner.)

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.

Tishana's Tidebinder

Flash
When this creature enters, counter up to one target activated or triggered ability. If an ability of an artifact, creature, or planeswalker is countered this way, that permanent loses all abilities for as long as this creature remains on the battlefield. (Mana abilities can't be targeted.)