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.
{U}
Aquitect's Will
Tribal Sorcery - Merfolk
Put a flood counter on target land. That land is an Island in addition to its other types for as long as it has a flood counter on it. If you control a Merfolk, draw a card.
{2}{U}{U}
Bident of Thassa
Legendary Enchantment Artifact
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.
{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
{U}{U}
Coralhelm Commander
Creature - Merfolk Soldier
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.
2 /
2
{1}{U}
Coralhelm Guide
Creature - Merfolk Scout Ally
{4}{U}: Target creature can't be blocked this turn.
2 /
1
{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.
{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
{3}{G}
Deeproot Historian
Creature - Merfolk Druid
Merfolk and Druid cards in your graveyard have retrace. (You may cast cards with retrace from your graveyard by discarding a land card in addition to paying their other costs.)
3 /
3
{1}{U}
Deeproot Pilgrimage
Enchantment
Whenever one or more nontoken Merfolk you control become tapped, create a 1/1 blue Merfolk creature token with hexproof.
{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.)
{1}{U}{U}
Emperor Mihail II
Legendary Creature - Merfolk Noble
You may look at the top card of your library any time.
You may cast Merfolk spells from the top of your library.
Whenever you cast a Merfolk spell, you may pay {1}. If you do, create a 1/1 blue Merfolk creature token.
3 /
3
--
Evolving Wilds
Land
{T}, Sacrifice Evolving Wilds: Search your library for a basic land card, put it onto the battlefield tapped, then shuffle.
{3}{U}
Fallowsage
Creature - Merfolk Wizard
Whenever Fallowsage becomes tapped, you may draw a card.
2 /
2
{1}{G}
Farseek
Sorcery
Search your library for a Plains, Island, Swamp, or Mountain card, put it onto the battlefield tapped, then shuffle.
{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}.)
--
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}.)
{G}{U}
Growth Spiral
Instant
Draw a card. You may put a land card from your hand onto the battlefield.
{G}
Hardened Scales
Enchantment
If one or more +1/+1 counters would be put on a creature you control, that many plus one +1/+1 counters are put on it instead.
{3}{U}
Herald of Secret Streams
Creature - Merfolk Warrior
Creatures you control with +1/+1 counters on them can't be blocked.
2 /
3
{2}{G}
Inspiring Call
Instant
Draw a card for each creature you control with a +1/+1 counter on it. Those creatures gain indestructible until end of turn. (Damage and effects that say "destroy" don't destroy them.)
{3}{U}
Irenicus's Vile Duplication
Sorcery
Create a token that's a copy of target creature you control, except the token has flying and it isn't legendary.
--
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}.)
{1}{G}{G}
Jadelight Ranger
Creature - Merfolk Scout Ranger
When Jadelight Ranger enters the battlefield, 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.)
2 /
1
{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
{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
{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}{G}
Merfolk Branchwalker
Creature - Merfolk Scout
When Merfolk Branchwalker enters the battlefield, 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.)
2 /
1
{G}{U}
Merfolk Mistbinder
Creature - Merfolk Shaman
Other Merfolk you control get +1/+1.
2 /
2
{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}{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
{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
{2}
Metallic Mimic
Artifact Creature - Shapeshifter
As Metallic Mimic enters the battlefield, choose a creature type.
Metallic Mimic is the chosen type in addition to its other types.
Each other creature you control of the chosen type enters the battlefield with an additional +1/+1 counter on it.
2 /
1
{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
--
Oran-Rief, the Vastwood
Land
Oran-Rief, the Vastwood enters the battlefield tapped.
{T}: Add {G}.
{T}: Put a +1/+1 counter on each green creature that entered the battlefield this turn.
{3}{G}{G}
Overwhelming Stampede
Sorcery
Until end of turn, creatures you control gain trample and get +X/+X, where X is the greatest power among creatures you control.
{2}{G}{G}{U}{U}
Prime Speaker Zegana
Legendary Creature - Merfolk Wizard
Prime Speaker Zegana enters the battlefield with X +1/+1 counters on it, where X is the greatest power among other creatures you control.
When Prime Speaker Zegana enters the battlefield, draw cards equal to its power.
1 /
1
{1}{U}{U}
Quasiduplicate
Sorcery
Create a token that's a copy of target creature you control.
Jump-start (You may cast this card from your graveyard by discarding a card in addition to paying its other costs. Then exile this card.)
{1}{G}
Rampant Growth
Sorcery
Search your library for a basic land card, put that card onto the battlefield tapped, then shuffle.
--
Reliquary Tower
Land
You have no maximum hand size.
{T}: Add {C}.
{4}{G}
Return of the Wildspeaker
Instant
Choose one --
• Draw cards equal to the greatest power among non-Human creatures you control.
• Non-Human creatures you control get +3/+3 until end of turn.
{U}
Rishadan Dockhand
Creature - Merfolk
Islandwalk (This creature can't be blocked as long as defending player controls an Island.)
{1}, {T}: Tap target land.
1 /
2
{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.
{2}{U}{U}
Seafloor Oracle
Creature - Merfolk Wizard
Whenever a Merfolk you control deals combat damage to a player, draw a card.
2 /
3
{1}{U}
Silvergill Adept
Creature - Merfolk Wizard
As an additional cost to cast this spell, reveal a Merfolk card from your hand or pay {3}.
When Silvergill Adept enters the battlefield, draw a card.
2 /
1
{1}
Sol Ring
Artifact
{T}: Add {C}{C}.
{1}{G}
Song of Freyalise
Enchantment - Saga
(As this Saga enters and after your draw step, add a lore counter. Sacrifice after III.)
I, II -- Until your next turn, creatures you control gain "{T}: Add one mana of any color."
III -- Put a +1/+1 counter on each creature you control. Those creatures gain vigilance, trample, and indestructible until end of turn.
{1}{U}
Spreading Seas
Enchantment - Aura
Enchant land
When Spreading Seas enters the battlefield, draw a card.
Enchanted land is an Island.
{1}
Stoneforge Masterwork
Artifact - Equipment
Equipped creature gets +1/+1 for each other creature you control that shares a creature type with it.
Equip {2}
{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
{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
{U}
Stubborn Denial
Instant
Counter target noncreature spell unless its controller pays {1}.
Ferocious -- If you control a creature with power 4 or greater, counter that spell instead.
{1}{G}{G}
Swift Warden
Creature - Merfolk Warrior
Flash
When Swift Warden enters the battlefield, target Merfolk you control gains hexproof until end of turn. (It can't be the target of spells or abilities your opponents control.)
3 /
3
{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
{2}{U}{U}
Tempest Caller
Creature - Merfolk Wizard
When Tempest Caller enters the battlefield, tap all creatures target opponent controls.
2 /
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}.
--
Terramorphic Expanse
Land
{T}, Sacrifice Terramorphic Expanse: Search your library for a basic land card, put it onto the battlefield tapped, then shuffle.
{2}
Throne of the God-Pharaoh
Legendary Artifact
At the beginning of your end step, each opponent loses life equal to the number of tapped creatures you control.
{3}{G}
Tributary Instructor
Creature - Merfolk Shaman
Mentor (Whenever this creature attacks, put a +1/+1 counter on target attacking creature with lesser power.)
Whenever a creature you control with a +1/+1 counter on it dies, draw a card.
4 /
4
{1}{G}{U}
Vorel of the Hull Clade
Legendary Creature - Human Merfolk
{G}{U}, {T}: Double the number of each kind of counter on target artifact, creature, or land.
1 /
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.
4 /
4
--
Bird
Token Creature - Bird
Blue
Flying
2 /
2
--
Copy
Token
Colorless
(This token can be used to represent a token that's a copy of a permanent.)
--
Merfolk
Token Creature - Merfolk
Blue
Hexproof (This creature can't be the target of spells or abilities your opponents control.)