Metallic Mimic

As this creature enters, choose a creature type.
This creature is the chosen type in addition to its other types.
Each other creature you control of the chosen type enters with an additional +1/+1 counter on it.

Prairie Stream

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

Minas Tirith

Minas Tirith enters tapped unless you control a legendary creature.
{T}: Add {W}.
{1}{W}, {T}: Draw a card. Activate only if you attacked with two or more creatures this turn.

Unexpected Assistance

Convoke (Your creatures can help cast this spell. Each creature you tap while casting this spell pays for {1} or one mana of that creature's color.)
Draw three cards, then discard a card.

Island

Lord of Atlantis

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

Cathars' Crusade

Whenever a creature you control enters, put a +1/+1 counter on each creature you control.

Day of Judgment

Protective Response

Convoke (Your creatures can help cast this spell. Each creature you tap while casting this spell pays for {1} or one mana of that creature's color.)
Destroy target attacking or blocking creature.

Run Away Together

Choose two target creatures controlled by different players. Return those creatures to their owners' hands.

Sol Ring

Dolmen Gate

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

Lyse Hext

Prowess (Whenever you cast a noncreature spell, this creature gets +1/+1 until end of turn.)
Noncreature spells you cast cost {1} less to cast.
As long as you've cast two or more noncreature spells this turn, Lyse Hext has double strike.

Absolute Virtue

This spell can't be countered.
Flying
You have protection from each of your opponents. (You can't be dealt damage, enchanted, or targeted by anything controlled by your opponents.)

Commander's Insignia

Creatures you control get +1/+1 for each time you've cast your commander from the command zone this game.

Tributary Vaulter

Flying
Whenever this creature becomes tapped, another target Merfolk you control gets +2/+0 until end of turn.

Renewed Solidarity

As this enchantment enters, choose a creature type.
Creatures you control of the chosen type get +1/+0.
At the beginning of your end step, for each token you control of the chosen type that entered this turn, create a token that's a copy of it.

Meanders Guide

Whenever this creature attacks, you may tap another untapped Merfolk you control. When you do, return target creature card with mana value 3 or less from your graveyard to the battlefield.

Gravelgill Scoundrel

Vigilance
Whenever this creature attacks, you may tap another untapped creature you control. If you do, this creature can't be blocked this turn.

Mistrise Village

This land enters tapped unless you control a Mountain or a Forest.
{T}: Add {U}.
{U}, {T}: The next spell you cast this turn can't be countered.

Abundant Countryside

{T}: Add {C}.
{T}: Add one mana of any color. Spend this mana only to cast a creature spell.
{6}, {T}: Create a 1/1 colorless Shapeshifter creature token with changeling. (It's every creature type.)

Shore Lurker

Flying
When this creature enters, surveil 1. (Look at the top card of your library. You may put it into your graveyard.)

Floodpits Drowner

Flash
Vigilance
When this creature enters, tap target creature an opponent controls and put a stun counter on it.
{1}{U}, {T}: Shuffle this creature and target creature with a stun counter on it into their owners' libraries.

An Offer You Can't Refuse

Counter target noncreature spell. Its controller creates two Treasure tokens. (They're artifacts with "{T}, Sacrifice this token: Add one mana of any color.")

Katara's Reversal

Counter up to four target spells and/or abilities.
Untap up to four target artifacts and/or creatures.

Tranquil Cove

This land enters tapped.
When this land enters, you gain 1 life.
{T}: Add {W} or {U}.

Harmonized Crescendo

Convoke (Your creatures can help cast this spell. Each creature you tap while casting this spell pays for {1} or one mana of that creature's color.)
Choose a creature type. Draw a card for each permanent you control of that type.

Silvergill Mentor

As an additional cost to cast this spell, behold a Merfolk or pay {2}. (To behold a Merfolk, choose a Merfolk you control or reveal a Merfolk from your hand.)
When this creature enters, create a 1/1 white and blue Merfolk creature token.

Vodalian Mage

{U}, {T}: Counter target spell unless its controller pays {1}.

Evolving Wilds

{T}, Sacrifice this land: Search your library for a basic land card, put it onto the battlefield tapped, then shuffle.

Empress Galina

{U}{U}, {T}: Gain control of target legendary permanent. (This effect lasts indefinitely.)

Sharlayan, Nation of Scholars

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

Abandoned Campground

This land enters tapped unless a player has 13 or less life.
{T}: Add {W} or {U}.

Arcane Signet

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

Encumbered Reejerey

This creature enters with three -1/-1 counters on it.
Whenever this creature becomes tapped while it has a -1/-1 counter on it, remove a -1/-1 counter from it.

Enduring Curiosity

Flash
Whenever a creature you control deals combat damage to a player, draw a card.
When Enduring Curiosity dies, if it was a creature, return it to the battlefield under its owner's control. It's an enchantment. (It's not a creature.)

Azorius Signet

Bident of Thassa

Whenever a creature you control deals combat damage to a player, you may draw a card.
{1}{U}, {T}: Creatures your opponents control attack this turn if able.

Rimefire Torque

As this artifact enters, choose a creature type.
Whenever a permanent you control of the chosen type enters, put a charge counter on this artifact.
{T}, Remove three charge counters from this artifact: When you next cast an instant or sorcery spell this turn, copy it. You may choose new targets for the copy.

Katara, Water Tribe's Hope

Vigilance
When Katara enters, create a 1/1 white Ally creature token.
Waterbend {X}: Creatures you control have base power and toughness X/X until end of turn. X can't be 0. Activate only during your turn. (While paying a waterbend cost, you can tap your artifacts and creatures to help. Each one pays for {1}.)

High Fae Trickster

Flash (You may cast this spell any time you could cast an instant.)
Flying
You may cast spells as though they had flash.

Silvergill Peddler

Whenever this creature becomes tapped, draw a card, then discard a card.

Hallowed Fountain

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

Cursecatcher

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

Spell Queller

Flash
Flying
When this creature enters, exile target spell with mana value 4 or less.
When this creature leaves the battlefield, the exiled card's owner may cast that card without paying its mana cost.

Deepway Navigator

Flash
When this creature enters, untap each other Merfolk you control.
As long as you attacked with three or more Merfolk this turn, Merfolk you control get +1/+0.

Vanquisher's Banner

As this artifact 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.

Wanderwine Distracter

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

Time Wipe

Return a creature you control to its owner's hand, then destroy all creatures.

Sygg, Wanderbrine Shield

Sygg can't be blocked.
Whenever this creature transforms into Sygg, Wanderbrine Shield, target creature you control gains protection from each color until your next turn.
At the beginning of your first main phase, you may pay {U}. If you do, transform Sygg.

Sygg, Wanderwine Wisdom

Sygg can't be blocked.
Whenever this creature enters or transforms into Sygg, Wanderwine Wisdom, target creature gains "Whenever this creature deals combat damage to a player or planeswalker, draw a card" until end of turn.
At the beginning of your first main phase, you may pay {W}. If you do, transform Sygg.

Sygg, Wanderwine Wisdom // Sygg, Wanderbrine Shield

Irrigated Farmland

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

Spell Pierce

Counter target noncreature spell unless its controller pays {2}.

Spell Snare

Flock Impostor

Changeling (This card is every creature type.)
Flash
Flying
When this creature enters, return up to one other target creature you control to its owner's hand.

Glacial Fortress

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

Get Lost

Destroy target creature, enchantment, or planeswalker. Its controller creates two Map tokens. (They're artifacts with "{1}, {T}, Sacrifice this token: Target creature you control explores. Activate only as a sorcery.")

Summon: Leviathan

(As this Saga enters and after your draw step, add a lore counter. Sacrifice after III.)
I — Return each creature that isn't a Kraken, Leviathan, Merfolk, Octopus, or Serpent to its owner's hand.
II, III — Until end of turn, whenever a Kraken, Leviathan, Merfolk, Octopus, or Serpent attacks, draw a card.
Ward {2}

Lofty Dreams

Convoke (Your creatures can help cast this spell. Each creature you tap while casting this spell pays for {1} or one mana of that creature's color.)
Enchant creature
When this Aura enters, draw a card.
Enchanted creature gets +2/+2 and has flying.

Thirst for Identity

Draw three cards. Then discard two cards unless you discard a creature card.

Champions of the Shoal

As an additional cost to cast this spell, behold a Merfolk and exile it. (Exile a Merfolk you control or a Merfolk card from your hand.)
Whenever this creature enters or becomes tapped, tap up to one target creature and put a stun counter on it.
When this creature leaves the battlefield, return the exiled card to its owner's hand.

Mirrormind Crown

As long as this Equipment is attached to a creature, the first time you would create one or more tokens each turn, you may instead create that many tokens that are copies of equipped creature.
Equip {2}

Riptide Gearhulk

Double strike
Prowess (Whenever you cast a noncreature spell, this creature gets +1/+1 until end of turn.)
When this creature enters, for each opponent, put up to one target nonland permanent that player controls into its owner's library third from the top.

Command Tower

Banner of Kinship

As this artifact enters, choose a creature type. This artifact enters with a fellowship counter on it for each creature you control of the chosen type.
Creatures you control of the chosen type get +1/+1 for each fellowship counter on this artifact.

Plains

Sygg's Command

Choose two —
• Create a token that's a copy of target Merfolk you control.
• Creatures target player controls gain lifelink until end of turn.
• Target player draws a card.
• Tap target creature. Put a stun counter on it.

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 this creature deals combat damage to a player, you may sacrifice a Merfolk. If you do, take an extra turn after this one.

Wanderbrine Preacher

Whenever this creature becomes tapped, you gain 2 life.

Glasspool Shore

Glasspool Mimic

You may have this creature enter as a copy of a creature you control, except it's a Shapeshifter Rogue in addition to its other types.

Glasspool Mimic // Glasspool Shore

Fabled Passage

{T}, Sacrifice this land: 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.

Dovin's Veto

This spell can't be countered.
Counter target noncreature spell.

Clone

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

Swords to Plowshares

Exile target creature. Its controller gains life equal to its power.

Sahagin

Whenever you cast a noncreature spell, if at least four mana was spent to cast it, put a +1/+1 counter on this creature and it can't be blocked this turn.

Chronicle of Victory

As Chronicle of Victory enters, choose a creature type.
Creatures you control of the chosen type get +2/+2 and have first strike and trample.
Whenever you cast a spell of the chosen type, draw a card.

Blossombind

Enchant creature
When this Aura enters, tap enchanted creature.
Enchanted creature can't become untapped and can't have counters put on it.

Spiral into Solitude

Enchant creature
Enchanted creature can't attack or block.
{1}{W}, Blight 1, Sacrifice this Aura: Exile enchanted creature. (To blight 1, put a -1/-1 counter on a creature you control.)

Pearl Medallion

White spells you cast cost {1} less to cast.

Celestial Colonnade

This land enters tapped.
{T}: Add {W} or {U}.
{3}{W}{U}: Until end of turn, this land becomes a 4/4 white and blue Elemental creature with flying and vigilance. It's still a land.

Counterspell

Wake Thrasher

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