Thoughtcutter Agent

{U}{B}, {T}: Target player loses 1 life and reveals their hand.

Morphic Pool

Morphic Pool enters the battlefield tapped unless you have two or more opponents.
{T}: Add {U} or {B}.

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 of your library.)

Lurking Informant

({U/B} can be paid with either {U} or {B}.)
{2}, {T}: Look at the top card of target player's library. You may put that card into that player's graveyard.

Darkwater Catacombs

Darkslick Shores

Darkslick Shores enters the battlefield tapped unless you control two or fewer other lands.
{T}: Add {U} or {B}.

Slip Through Space

Devoid (This card has no color.)
Target creature can't be blocked this turn.
Draw a card.

Nighthawk Scavenger

Flying, deathtouch, lifelink
Nighthawk Scavenger's power is equal to 1 plus the number of card types among cards in your opponents' graveyards.

Pulse Tracker

Whenever Pulse Tracker attacks, each opponent loses 1 life.

Library Larcenist

Whenever Library Larcenist attacks, draw a card.

Command Tower

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

Shadowmage Infiltrator

Fear (This creature can't be blocked except by artifact creatures and/or black creatures.)
Whenever Shadowmage Infiltrator deals combat damage to a player, you may draw a card.

Hullbreacher

Flash
If an opponent would draw a card except the first one they draw in each of their draw steps, instead you create a Treasure token. (It's an artifact with "{T}, Sacrifice this artifact: Add one mana of any color.")

Invisible Stalker

Hexproof (This creature can't be the target of spells or abilities your opponents control.)
Invisible Stalker can't be blocked.

Wanderwine Prophets

Champion a Merfolk (When this enters the battlefield, 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.

Merrow Witsniper

When Merrow Witsniper enters the battlefield, target player mills a card.

Merfolk Spy

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

Access Tunnel

{T}: Add {C}.
{3}, {T}: Target creature with power 3 or less can't be blocked this turn.

Oboro, Palace in the Clouds

{T}: Add {U}.
{1}: Return Oboro, Palace in the Clouds to its owner's hand.

Sygg, River Cutthroat

At the beginning of each end step, if an opponent lost 3 or more life this turn, you may draw a card. (Damage causes loss of life.)

Inkfathom Infiltrator

Inkfathom Infiltrator can't block and can't be blocked.

Thieves' Guild Enforcer

Flash
Whenever Thieves' Guild Enforcer or another Rogue enters the battlefield under your control, each opponent mills two cards.
As long as an opponent has eight or more cards in their graveyard, Thieves' Guild Enforcer gets +2/+1 and has deathtouch.

Island

Merrow Commerce

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

Oona's Blackguard

Flying
Each other Rogue creature you control enters the battlefield with an additional +1/+1 counter on it.
Whenever a creature you control with a +1/+1 counter on it deals combat damage to a player, that player discards a card.

Seafloor Oracle

Whenever a Merfolk you control deals combat damage to a player, draw a card.

Harbor Bandit

Harbor Bandit gets +1/+1 as long as you control an Island.
{1}{U}: Harbor Bandit can't be blocked this turn.

Kaya's Ghostform

Enchant creature or planeswalker you control
When enchanted permanent dies or is put into exile, return that card to the battlefield under your control.

Rootwater Matriarch

{T}: Gain control of target creature for as long as that creature is enchanted.

Deathcult Rogue

Deathcult Rogue can't be blocked except by Rogues.

Wake Thrasher

Whenever a permanent you control becomes untapped, Wake Thrasher gets +1/+1 until end of turn.

Stealer of Secrets

Whenever Stealer of Secrets deals combat damage to a player, draw a card.

Shadow Alley Denizen

Whenever another black creature enters the battlefield under your control, target creature gains intimidate until end of turn. (It can't be blocked except by artifact creatures and/or creatures that share a color with it.)

Sandbar Merfolk

Cycling {2} ({2}, Discard this card: Draw a card.)

River Sneak

River Sneak can't be blocked.
Whenever another Merfolk enters the battlefield under your control, River Sneak gets +1/+1 until end of turn.

Shizo, Death's Storehouse

{T}: Add {B}.
{B}, {T}: Target legendary creature gains fear until end of turn. (It can't be blocked except by artifact creatures and/or black creatures.)

Reliquary Tower

You have no maximum hand size.
{T}: Add {C}.

Castle Locthwain

Castle Locthwain enters the battlefield tapped unless you control a Swamp.
{T}: Add {B}.
{1}{B}{B}, {T}: Draw a card, then you lose life equal to the number of cards in your hand.

Rogue's Passage

{T}: Add {C}.
{4}, {T}: Target creature can't be blocked this turn.

Vampire Cutthroat

Skulk (This creature can't be blocked by creatures with greater power.)
Lifelink (Damage dealt by this creature also causes you to gain that much life.)

Rogue's Gloves

Whenever equipped creature deals combat damage to a player, you may draw a card.
Equip {2} ({2}: Attach to target creature you control. Equip only as a sorcery.)

Herald of Secret Streams

Creatures you control with +1/+1 counters on them can't be blocked.

Ancient Tomb

{T}: Add {C}{C}. Ancient Tomb deals 2 damage to you.

Hada Spy Patrol

Level up {2}{U} ({2}{U}: Put a level counter on this. Level up only as a sorcery.)
LEVEL 1-2
2/2
Hada Spy Patrol can't be blocked.
LEVEL 3+
3/3
Shroud (This creature can't be the target of spells or abilities.)
Hada Spy Patrol can't be blocked.

Rankle, Master of Pranks

Flying, haste
Whenever Rankle, Master of Pranks deals combat damage to a player, choose any number —
• Each player discards a card.
• Each player loses 1 life and draws a card.
• Each player sacrifices a creature.

Cloak of Mists

Enchant creature
Enchanted creature can't be blocked.

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 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.

Castle Vantress

Castle Vantress enters the battlefield tapped unless you control an Island.
{T}: Add {U}.
{2}{U}{U}, {T}: Scry 2.

Riptide Pilferer

Whenever Riptide Pilferer deals combat damage to a player, that player discards a card.
Morph {U} (You may cast this card face down as a 2/2 creature for {3}. Turn it face up any time for its morph cost.)

Keeper of Keys

When Keeper of Keys enters the battlefield, you become the monarch.
At the beginning of your upkeep, if you're the monarch, creatures you control can't be blocked this turn.

Marchesa's Infiltrator

Dethrone (Whenever this creature attacks the player with the most life or tied for most life, put a +1/+1 counter on it.)
Whenever Marchesa's Infiltrator deals combat damage to a player, draw a card.

Tidal Kraken

Marchesa's Emissary

Hexproof (This creature can't be the target of spells or abilities your opponents control.)
Dethrone (Whenever this creature attacks the player with the most life or tied for most life, put a +1/+1 counter on it.)

Minamo, School at Water's Edge

{T}: Add {U}.
{U}, {T}: Untap target legendary permanent.

Thassa's Oracle

When Thassa's Oracle enters the battlefield, look at the top X cards of your library, where X is your devotion to blue. Put up to one of them on top of your library and the rest on the bottom of your library in a random order. If X is greater than or equal to the number of cards in your library, you win the game. (Each {U} in the mana costs of permanents you control counts toward your devotion to blue.)

Enclave Cryptologist

Level up {1}{U} ({1}{U}: Put a level counter on this. Level up only as a sorcery.)
LEVEL 1-2
0/1
{T}: Draw a card, then discard a card.
LEVEL 3+
0/1
{T}: Draw a card.

Triton Shorestalker

Marang River Prowler

Marang River Prowler can't block and can't be blocked.
You may cast Marang River Prowler from your graveyard as long as you control a black or green permanent.

Drowner Initiate

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

Deepchannel Mentor

Blue creatures you control can't be blocked.

Tetsuko Umezawa, Fugitive

Creatures you control with power or toughness 1 or less can't be blocked.

Drowned Catacomb

Drowned Catacomb enters the battlefield tapped unless you control an Island or a Swamp.
{T}: Add {U} or {B}.

Exotic Orchard

{T}: Add one mana of any color that a land an opponent controls could produce.

Key to the City

{T}, Discard a card: Up to one target creature can't be blocked this turn.
Whenever Key to the City becomes untapped, you may pay {2}. If you do, draw a card.

Distortion Strike

Target creature gets +1/+0 until end of turn and can't be blocked this turn.
Rebound (If you cast this spell from your hand, exile it as it resolves. At the beginning of your next upkeep, you may cast this card from exile without paying its mana cost.)

Slither Blade

Nykthos, Shrine to Nyx

{T}: Add {C}.
{2}, {T}: Choose a color. Add an amount of mana of that color equal to your devotion to that color. (Your devotion to a color is the number of mana symbols of that color in the mana costs of permanents you control.)

Whispersilk Cloak

Equipped creature can't be blocked and has shroud. (It can't be the target of spells or abilities.)
Equip {2}

Bojuka Bog

Bojuka Bog enters the battlefield tapped.
When Bojuka Bog enters the battlefield, exile target player's graveyard.
{T}: Add {B}.

Neurok Spy

Neurok Spy can't be blocked as long as defending player controls an artifact.

Mist-Cloaked Herald

Choked Estuary

As Choked Estuary enters the battlefield, you may reveal an Island or Swamp card from your hand. If you don't, Choked Estuary enters the battlefield tapped.
{T}: Add {U} or {B}.

Snow-Covered Swamp

Aether Tunnel

Enchant creature
Enchanted creature gets +1/+0 and can't be blocked.

Fabled Passage

{T}, Sacrifice Fabled Passage: Search your library for a basic land card, put it onto the battlefield tapped, then shuffle. Then if you control four or more lands, untap that land.

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.

Murkwater Pathway

Clearwater Pathway

Clearwater Pathway // Murkwater Pathway

Ghostform

Up to two target creatures can't be blocked this turn.

Cunning Nightbonder

Flash
Spells with flash you cast cost {1} less to cast and can't be countered.

Prickly Boggart

Fear (This creature can't be blocked except by artifact creatures and/or black creatures.)