When Aquatic Incursion enters the battlefield, 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.
{2}
Arcane Signet
Artifact
{T}: Add one mana of any color in your commander's color identity.
{2}{G}
Beast Within
Instant
Destroy target permanent. Its controller creates a 3/3 green Beast creature token.
{1}{G/U}{G/U}
Cold-Eyed Selkie
Creature - Merfolk Rogue
Islandwalk (This creature can't be blocked as long as defending player controls an Island.)
Whenever Cold-Eyed Selkie deals combat damage to a player, you may draw that many cards.
1 /
1
--
Command Tower
Land
{T}: Add one mana of any color in your commander's color identity.
{U}{U}
Counterspell
Instant
Counter target spell.
{2}{G}
Cultivate
Sorcery
Search your library for up to two basic land cards, reveal those cards, put one onto the battlefield tapped and the other into your hand, then shuffle.
{1}{G}
Curse of Bounty
Enchantment - Aura Curse
Enchant player
Whenever enchanted player is attacked, untap all nonland permanents you control. Each opponent attacking that player untaps all nonland permanents they control.
{5}{U}
Deepchannel Mentor
Creature - Merfolk Rogue
Blue creatures you control can't be blocked.
2 /
2
{1}{G}
Deeproot Elite
Creature - Merfolk Warrior
Whenever another Merfolk enters the battlefield under your control, put a +1/+1 counter on target Merfolk you control.
1 /
1
{2}{U}
Deeproot Waters
Enchantment
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.)
{3}{U}
Distant Melody
Sorcery
Choose a creature type. Draw a card for each permanent you control of that type.
{4}
Door of Destinies
Artifact
As Door of Destinies enters the battlefield, choose a creature type.
Whenever you cast a spell of the chosen type, put a charge counter on Door of Destinies.
Creatures you control of the chosen type get +1/+1 for each charge counter on Door of Destinies.
--
Dreamroot Cascade
Land
Dreamroot Cascade enters the battlefield tapped unless you control two or more other lands.
{T}: Add {G} or {U}.
{U}
Enclave Cryptologist
Creature - Merfolk Wizard
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.
0 /
1
{3}{U}
Fallowsage
Creature - Merfolk Wizard
Whenever Fallowsage becomes tapped, you may draw a card.
2 /
2
{3}{G}
Forerunner of the Heralds
Creature - Merfolk Scout
When Forerunner of the Heralds enters the battlefield, you may search your library for a Merfolk card, reveal it, then shuffle and put that card on top.
Whenever another Merfolk enters the battlefield under your control, put a +1/+1 counter on Forerunner of the Heralds.
3 /
2
--
Forest
Basic Land - Forest
({T}: Add {G}.)
--
Forest
Basic Land - Forest
({T}: Add {G}.)
--
Forest
Basic Land - Forest
({T}: Add {G}.)
--
Forest
Basic Land - Forest
({T}: Add {G}.)
--
Forest
Basic Land - Forest
({T}: Add {G}.)
--
Forest
Basic Land - Forest
({T}: Add {G}.)
{1}{U}
Gray Harbor Merfolk
Creature - Merfolk Rogue
Gray Harbor Merfolk can't be blocked.
Gray Harbor Merfolk gets +2/+0 as long as you control a commander that's a creature or planeswalker.
0 /
3
{2}{G}
Growing Rites of Itlimoc
Legendary Enchantment
When Growing Rites of Itlimoc enters the battlefield, look at the top four 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 any order.
At the beginning of your end step, if you control four or more creatures, transform Growing Rites of Itlimoc.
--
Itlimoc, Cradle of the Sun
Legendary Land
(Transforms from Growing Rites of Itlimoc.)
{T}: Add {G}.
{T}: Add {G} for each creature you control.
{G}{U}
Growth Spiral
Instant
Draw a card. You may put a land card from your hand onto the battlefield.
{1}{G}{U}
Hadana's Climb
Legendary Enchantment
At the beginning of combat on your turn, put a +1/+1 counter on target creature you control. Then if that creature has three or more +1/+1 counters on it, transform Hadana's Climb.
--
Winged Temple of Orazca
Legendary Land
(Transforms from Hadana's Climb.)
{T}: Add one mana of any color.
{1}{G}{U}, {T}: Target creature you control gains flying and gets +X/+X until end of turn, where X is its power.
{1}{G}{U}
Hadana's Climb
Legendary Enchantment
At the beginning of combat on your turn, put a +1/+1 counter on target creature you control. Then if that creature has three or more +1/+1 counters on it, transform Hadana's Climb.
--
Winged Temple of Orazca
Legendary Land
(Transforms from Hadana's Climb.)
{T}: Add one mana of any color.
{1}{G}{U}, {T}: Target creature you control gains flying and gets +X/+X until end of turn, where X is its power.
{2}{G}
Harvest Season
Sorcery
Search your library for up to X basic land cards, where X is the number of tapped creatures you control, put those cards onto the battlefield tapped, then shuffle.
{3}{U}
Herald of Secret Streams
Creature - Merfolk Warrior
Creatures you control with +1/+1 counters on them can't be blocked.
2 /
3
{3}
Herald's Horn
Artifact
As Herald's Horn enters the battlefield, choose a creature type.
Creature spells you cast of the chosen type cost {1} less to cast.
At the beginning of your upkeep, look at the top card of your library. If it's a creature card of the chosen type, you may reveal it and put it into your hand.
--
Hinterland Harbor
Land
Hinterland Harbor enters the battlefield tapped unless you control a Forest or an Island.
{T}: Add {G} or {U}.
--
Island
Basic Land - Island
({T}: Add {U}.)
--
Island
Basic Land - Island
({T}: Add {U}.)
--
Island
Basic Land - Island
({T}: Add {U}.)
--
Island
Basic Land - Island
({T}: Add {U}.)
--
Island
Basic Land - Island
({T}: Add {U}.)
--
Island
Basic Land - Island
({T}: Add {U}.)
--
Island
Basic Land - Island
({T}: Add {U}.)
--
Island
Basic Land - Island
({T}: Add {U}.)
--
Island
Basic Land - Island
({T}: Add {U}.)
--
Island
Basic Land - Island
({T}: Add {U}.)
--
Island
Basic Land - Island
({T}: Add {U}.)
--
Island
Basic Land - Island
({T}: Add {U}.)
--
Island
Basic Land - Island
({T}: Add {U}.)
--
Island
Basic Land - Island
({T}: Add {U}.)
{3}{U}{U}
Kindred Discovery
Enchantment
As Kindred Discovery enters the battlefield, choose a creature type.
Whenever a creature you control of the chosen type enters the battlefield or attacks, draw a card.
{5}{G}{G}
Kindred Summons
Instant
Choose a creature type. Reveal cards from the top of your library until you reveal X creature cards of the chosen type, where X is the number of creatures you control of that type. Put those cards onto the battlefield, then shuffle the rest of the revealed cards into your library.
{G}{U}
Kiora's Follower
Creature - Merfolk
{T}: Untap another target permanent.
2 /
2
{2}{G}
Kodama's Reach
Sorcery - Arcane
Search your library for up to two basic land cards, reveal those cards, put one onto the battlefield tapped and the other into your hand, then shuffle.
{1}{U}{U}
Kopala, Warden of Waves
Legendary Creature - Merfolk Wizard
Spells your opponents cast that target a Merfolk you control cost {2} more to cast.
Abilities your opponents activate that target a Merfolk you control cost {2} more to activate.
2 /
2
{2}{G}
Krosan Grip
Instant
Split second (As long as this spell is on the stack, players can't cast spells or activate abilities that aren't mana abilities.)
Destroy target artifact or enchantment.
{2}{U}{U}
Kumena's Awakening
Enchantment
Ascend (If you control ten or more permanents, you get the city's blessing for the rest of the game.)
At the beginning of your upkeep, each player draws a card. If you have the city's blessing, instead only you draw a card.
{1}{G}{U}
Kumena, Tyrant of Orazca
Legendary Creature - Merfolk Shaman
Tap another untapped Merfolk you control: Kumena, Tyrant of Orazca can't be blocked this turn.
Tap three untapped Merfolk you control: Draw a card.
Tap five untapped Merfolk you control: Put a +1/+1 counter on each Merfolk you control.
2 /
4
{2}
Lightning Greaves
Artifact - Equipment
Equipped creature has haste and shroud. (It can't be the target of spells or abilities.)
Equip {0}
{U}{U}
Lord of Atlantis
Creature - Merfolk
Other Merfolk get +1/+1 and have islandwalk. (They can't be blocked as long as defending player controls an Island.)
2 /
2
{U}{U}
Master of the Pearl Trident
Creature - Merfolk
Other Merfolk creatures you control get +1/+1 and have islandwalk. (They can't be blocked as long as defending player controls an Island.)
2 /
2
{1}{U}
Merfolk Looter
Creature - Merfolk Rogue
{T}: Draw a card, then discard a card.
1 /
1
{G}{U}
Merfolk Mistbinder
Creature - Merfolk Shaman
Other Merfolk you control get +1/+1.
2 /
2
{G}{U}
Merfolk Skydiver
Creature - Merfolk Mutant
Flying
When Merfolk Skydiver enters the battlefield, put a +1/+1 counter on target creature you control.
{3}{G}{U}: Proliferate. (Choose any number of permanents and/or players, then give each another counter of each kind already there.)
1 /
1
{1}{U}{U}
Merfolk Sovereign
Creature - Merfolk Noble
Other Merfolk creatures you control get +1/+1.
{T}: Target Merfolk creature can't be blocked this turn.
2 /
2
{U}
Merfolk of the Pearl Trident
Creature - Merfolk
1 /
1
{1}{U}
Merrow Commerce
Tribal Enchantment - Merfolk
At the beginning of your end step, untap all Merfolk you control.
{3}{U}
Merrow Harbinger
Creature - Merfolk Wizard
Islandwalk (This creature can't be blocked as long as defending player controls an Island.)
When Merrow Harbinger enters the battlefield, you may search your library for a Merfolk card, reveal it, then shuffle and put that card on top.
2 /
3
{2}{U}
Merrow Reejerey
Creature - Merfolk Soldier
Other Merfolk creatures you control get +1/+1.
Whenever you cast a Merfolk spell, you may tap or untap target permanent.
2 /
2
{U}
Mist-Cloaked Herald
Creature - Merfolk Warrior
Mist-Cloaked Herald can't be blocked.
1 /
1
{2}{G/U}{G/U}{G/U}
Murkfiend Liege
Creature - Horror
Other green creatures you control get +1/+1.
Other blue creatures you control get +1/+1.
Untap all green and/or blue creatures you control during each other player's untap step.
4 /
4
--
Path of Ancestry
Land
Path of Ancestry enters the battlefield tapped.
{T}: Add one mana of any color in your commander's color identity. When that mana is spent to cast a creature spell that shares a creature type with your commander, scry 1. (Look at the top card of your library. You may put that card on the bottom.)
{U}
Pongify
Instant
Destroy target creature. It can't be regenerated. Its controller creates a 3/3 green Ape creature token.
{1}{G}
Quest for Renewal
Enchantment
Whenever a creature you control becomes tapped, you may put a quest counter on Quest for Renewal.
As long as there are four or more quest counters on Quest for Renewal, untap all creatures you control during each other player's untap step.
{1}{G}
Rampant Growth
Sorcery
Search your library for a basic land card, put that card onto the battlefield tapped, then shuffle.
{U}
Rapid Hybridization
Instant
Destroy target creature. It can't be regenerated. That creature's controller creates a 3/3 green Frog Lizard creature token.
{4}{U}
Reflections of Littjara
Enchantment
As Reflections of Littjara enters the battlefield, choose a creature type.
Whenever you cast a spell of the chosen type, copy that spell. (A copy of a permanent spell becomes a token.)
--
Rejuvenating Springs
Land
Rejuvenating Springs enters the battlefield tapped unless you have two or more opponents.
{T}: Add {G} or {U}.
--
Reliquary Tower
Land
You have no maximum hand size.
{T}: Add {C}.
{2}{U}{U}
Rite of Replication
Sorcery
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.
{1}{G}
River Heralds' Boon
Instant
Put a +1/+1 counter on target creature and a +1/+1 counter on up to one target Merfolk.
{4}{U}{U}
River's Rebuke
Sorcery
Return all nonland permanents target player controls to their owner's hand.
{2}{U}{U}
Seafloor Oracle
Creature - Merfolk Wizard
Whenever a Merfolk you control deals combat damage to a player, draw a card.
2 /
3
--
Secluded Courtyard
Land
As Secluded Courtyard enters the battlefield, choose a creature type.
{T}: Add {C}.
{T}: Add one mana of any color. Spend this mana only to cast a creature spell of the chosen type or activate an ability of a creature source of the chosen type.
{3}{G}{G}
Seedborn Muse
Creature - Spirit
Untap all permanents you control during each other player's untap step.
2 /
4
{1}{U}
Silvergill Douser
Creature - Merfolk Wizard
{T}: Target creature gets -X/-0 until end of turn, where X is the number of Merfolk and/or Faeries you control.
1 /
1
{G}{U}
Simic Ascendancy
Enchantment
{1}{G}{U}: Put a +1/+1 counter on target creature you control.
Whenever one or more +1/+1 counters are put on a creature you control, put that many growth counters on Simic Ascendancy.
At the beginning of your upkeep, if Simic Ascendancy has twenty or more growth counters on it, you win the game.
--
Simic Growth Chamber
Land
Simic Growth Chamber enters the battlefield tapped.
When Simic Growth Chamber enters the battlefield, return a land you control to its owner's hand.
{T}: Add {G}{U}.
{2}
Simic Signet
Artifact
{1}, {T}: Add {G}{U}.
{1}
Sol Ring
Artifact
{T}: Add {C}{C}.
{1}{U}
Stonybrook Banneret
Creature - Merfolk Wizard
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.
1 /
1
{2}{U}{U}
Surgespanner
Creature - Merfolk Wizard
Whenever Surgespanner becomes tapped, you may pay {1}{U}. If you do, return target permanent to its owner's hand.
2 /
2
{1}{U}{U}
Svyelun of Sea and Sky
Legendary Creature - Merfolk God
Svyelun of Sea and Sky has indestructible as long as you control at least two other Merfolk.
Whenever Svyelun attacks, draw a card.
Other Merfolk you control have ward {1}. (Whenever another Merfolk you control becomes the target of a spell or ability an opponent controls, counter it unless that player pays {1}.)
3 /
4
{2}
Talisman of Curiosity
Artifact
{T}: Add {C}.
{T}: Add {G} or {U}. Talisman of Curiosity deals 1 damage to you.
{3}{G}{U}
Tatyova, Benthic Druid
Legendary Creature - Merfolk Druid
Landfall -- Whenever a land enters the battlefield under your control, you gain 1 life and draw a card.
3 /
3
--
Temple of Mystery
Land
Temple of Mystery enters the battlefield tapped.
When Temple of Mystery enters the battlefield, scry 1.
{T}: Add {G} or {U}.
--
Temple of the False God
Land
{T}: Add {C}{C}. Activate only if you control five or more lands.
{1}{U}{U}
Thada Adel, Acquisitor
Legendary Creature - Merfolk Rogue
Islandwalk (This creature can't be blocked as long as defending player controls an Island.)
Whenever Thada Adel, Acquisitor deals combat damage to a player, search that player's library for an artifact card and exile it. Then that player shuffles. Until end of turn, you may play that card.
2 /
2
{5}{G}{U}
Tishana, Voice of Thunder
Legendary Creature - Merfolk Shaman
Tishana, Voice of Thunder's power and toughness are each equal to the number of cards in your hand.
You have no maximum hand size.
When Tishana enters the battlefield, draw a card for each creature you control.
* /
*
{1}{U}{U}
True-Name Nemesis
Creature - Merfolk Rogue
As True-Name Nemesis enters the battlefield, choose a player.
True-Name Nemesis has protection from the chosen player.
3 /
1
--
Unclaimed Territory
Land
As Unclaimed Territory enters the battlefield, choose a creature type.
{T}: Add {C}.
{T}: Add one mana of any color. Spend this mana only to cast a creature spell of the chosen type.
{5}
Vanquisher's Banner
Artifact
As Vanquisher's Banner enters the battlefield, 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.
{U}
Wizard Class
Enchantment - Class
(Gain the next level as a sorcery to add its ability.)
You have no maximum hand size.
{2}{U}: Level 2
When this Class becomes level 2, draw two cards.
{4}{U}: Level 3
Whenever you draw a card, put a +1/+1 counter on target creature you control.
--
Yavimaya Coast
Land
{T}: Add {C}.
{T}: Add {G} or {U}. Yavimaya Coast deals 1 damage to you.
--
Breeding Pool
Land - Forest Island
({T}: Add {G} or {U}.)
As Breeding Pool enters the battlefield, you may pay 2 life. If you don't, it enters the battlefield tapped.
{3}{U}{U}
Empress Galina
Legendary Creature - Merfolk Noble
{U}{U}, {T}: Gain control of target legendary permanent. (This effect lasts indefinitely.)
1 /
3
{2}{G}
Jungleborn Pioneer
Creature - Merfolk Scout
When Jungleborn Pioneer enters the battlefield, create a 1/1 blue Merfolk creature token with hexproof. (It can't be the target of spells or abilities your opponents control.)
2 /
2
{3}{U}
Master of Waves
Creature - Merfolk Wizard
Protection from red
Elemental creatures you control get +1/+1.
When Master of Waves enters the battlefield, create a number of 1/0 blue Elemental creature tokens equal to your devotion to blue. (Each {U} in the mana costs of permanents you control counts toward your devotion to blue.)
2 /
1
{U}{U}
Merfolk Trickster
Creature - Merfolk Wizard
Flash
When Merfolk Trickster enters the battlefield, tap target creature an opponent controls. It loses all abilities until end of turn.
2 /
2
{1}{U}
Negate
Instant
Counter target noncreature spell.
{1}{U}
River Sneak
Creature - Merfolk Warrior
River Sneak can't be blocked.
Whenever another Merfolk enters the battlefield under your control, River Sneak gets +1/+1 until end of turn.
1 /
1
{2}{U}{U}
Seahunter
Creature - Human Mercenary
{3}, {T}: Search your library for a Merfolk permanent card, put it onto the battlefield, then shuffle.
2 /
2
{1}{G}{U}
Shapers of Nature
Creature - Merfolk Shaman
{3}{G}: Put a +1/+1 counter on target creature.
{2}{U}, Remove a +1/+1 counter from a creature you control: Draw a card.
3 /
3
{6}{U}{U}
Slinn Voda, the Rising Deep
Legendary Creature - Leviathan
Kicker {1}{U} (You may pay an additional {1}{U} as you cast this spell.)
When Slinn Voda, the Rising Deep enters the battlefield, if it was kicked, return all creatures to their owners' hands except for Merfolk, Krakens, Leviathans, Octopuses, and Serpents.
8 /
8
{1}{U}{U}
Streambed Aquitects
Creature - Merfolk Scout
{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.
2 /
3
{G}{U}
Thrasios, Triton Hero
Legendary Creature - Merfolk Wizard
{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.)
1 /
3
{2}{G}
Vineshaper Mystic
Creature - Merfolk Shaman
When Vineshaper Mystic enters the battlefield, put a +1/+1 counter on each of up to two target Merfolk you control.
1 /
3
{4}{U}{U}
Wanderwine Prophets
Creature - Merfolk Wizard
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.
4 /
4
{2}{G}{U}
Zegana, Utopian Speaker
Legendary Creature - Merfolk Wizard
When Zegana, Utopian Speaker enters the battlefield, if you control another creature with a +1/+1 counter on it, draw a card.
{4}{G}{U}: Adapt 4. (If this creature has no +1/+1 counters on it, put four +1/+1 counters on it.)
Each creature you control with a +1/+1 counter on it has trample.