Look at the top three cards of your library. Put one of them into your hand and the rest on the bottom of your library in any order.

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.

Draw three cards, then put two cards from your hand on top of your library in any order.

When Cascade Seer enters the battlefield, 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.)

When Cenote Scout 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.)

Whenever Cleric of Chill Depths blocks a creature, that creature doesn't untap during its controller's next untap step.

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.

{U}, {T}: Each player reveals the top card of their library. You may put the revealed cards into their owners' graveyards. If you don't, each player draws a card.

At the beginning of combat on your turn, Deepfathom Echo explores. Then you may have it become a copy of another creature you control until end of turn. (To have this creature explore, 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.)

Whenever another Merfolk enters the battlefield under your control, put a +1/+1 counter on target Merfolk you control.

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.)

Counter target spell. Scry 1. (Look at the top card of your library. You may put that card on the bottom of your library.)

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.

At the beginning of combat on your turn, you may collect evidence 4. (Exile cards with total mana value 4 or greater from your graveyard.)

Whenever you collect evidence, investigate. (Create a Clue token. It's an artifact with "{2}, Sacrifice this artifact: Draw a card.")

Flying

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

({T}: Add {G}.)

({T}: Add {G}.)

({T}: Add {G}.)

({T}: Add {G}.)

({T}: Add {G}.)

({T}: Add {G}.)

({T}: Add {G}.)

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({T}: Add {G}.)

({T}: Add {G}.)

({T}: Add {G}.)

({T}: Add {G}.)

({T}: Add {G}.)

({T}: Add {G}.)

({T}: Add {G}.)

({T}: Add {G}.)

({T}: Add {G}.)

({T}: Add {G}.)

({T}: Add {G}.)

Giltgrove Stalker can't be blocked by creatures with power 2 or less.

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.

At the beginning of combat on your turn, each Merfolk creature you control 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 the exploring creature, then put the card back or put it into your graveyard.)

Whenever Hakbal of the Surging Soul attacks, you may put a land card from your hand onto the battlefield. If you don't, draw a card.

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.

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.)

({T}: Add {U}.)

({T}: Add {U}.)

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({T}: Add {U}.)

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({T}: Add {U}.)

When Jade Bearer enters the battlefield, put a +1/+1 counter on another target Merfolk you control.

When Jadecraft Artisan enters the battlefield, target creature gets +2/+2 until end of turn.

When Jadelight Spelunker enters the battlefield, it explores X times. (To have it explore, 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.)

{3}{G}: Put a +1/+1 counter on Jungle Delver.

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.)

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.

Other Merfolk you control get +1/+1.

Other Merfolk creatures you control get +1/+1.

{T}: Target Merfolk creature can't be blocked this turn.

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.

Other Merfolk creatures you control get +1/+1.

Whenever you cast a Merfolk spell, you may tap or untap target permanent.

Mist-Cloaked Herald can't be blocked.

Flying

Disguise {1}{U} (You may cast this card face down for {3} as a 2/2 creature with ward {2}. Turn it face up any time for its disguise cost.)

When Mistway Spy is turned face up, until end of turn, whenever a creature you control deals combat damage to a player, investigate.

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

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, Current Conductor.

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.

Put X +1/+1 counters on target creature you control. Then counter up to one target spell unless its controller pays mana equal to the greatest power among creatures you control.

Landfall -- Whenever a land enters the battlefield under your control, choose one --

• You may tap or untap target creature.

• Scry 1. (Look at the top card of your library. You may put that card on the bottom of your library.)

Vigilance

When River Herald Guide 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.)

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

Whenever Scroll Thief deals combat damage to a player, draw a card.

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

{4}{U}: Seafloor Stalker 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.)

{2}{G}: Seeker of Sunlight 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.)

Evolve (Whenever a creature enters the battlefield under your control, if that creature has greater power or toughness than this creature, put a +1/+1 counter on this creature.)

{1}{U}, {T}: Move a +1/+1 counter from Simic Fluxmage onto target creature.

{T}: Add {C}{C}.

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}.)

Landfall -- Whenever a land enters the battlefield under your control, you gain 1 life and draw a card.

Kicker {4} (You may pay an additional {4} as you cast this spell.)

When Tazeem Roilmage enters the battlefield, if it was kicked, return target instant or sorcery card from your graveyard to your hand.

Draw three cards. Target player mills three cards.

When The Everflowing Well enters the battlefield, mill two cards, then draw two cards.

Descend 8 -- At the beginning of your upkeep, if there are eight or more permanent cards in your graveyard, transform The Everflowing Well.

(Transforms from The Everflowing Well.)

{T}: Add {U}.

Whenever you cast a permanent spell using mana produced by The Myriad Pools, up to one other target permanent you control becomes a copy of that spell until end of turn.

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

If a creature you control would explore, instead it explores, then it explores again.

Heroic -- Whenever you cast a spell that targets Triton Cavalry, you may return target enchantment to its owner's hand.

Heroic -- Whenever you cast a spell that targets Triton Fortune Hunter, draw a card.

Triton Shorestalker can't be blocked.

Up to two target creatures each get +0/+3 until end of turn. Untap those creatures. At this turn's next end of combat, tap each creature that was blocked by one of those creatures this turn and it doesn't untap during its controller's next untap step.

Prowess (Whenever you cast a noncreature spell, this creature gets +1/+1 until end of turn.)

Whenever a creature you control explores, put a +1/+1 counter on Wildgrowth Walker and you gain 3 life.

Flying

Whenever Windrider Patrol 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 of your library and the rest on top in any order.)

Defender

{1}{U}: Wishful Merfolk loses defender and becomes a Human until end of turn.

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.