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.

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.

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.

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

Blue creatures you control can't be blocked.

Whenever you cast a noncreature spell, put a +1/+1 counter on Deeproot Champion.

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

Whenever Deeproot Wayfinder deals combat damage to a player or battle, surveil 1, then you may return a land card from your graveyard to the battlefield tapped. (To surveil 1, look at the top card of your library. You may put that card into your graveyard.)

Flash Emerge {5}{U}{U} (You may cast this spell by sacrificing a creature and paying the emerge cost reduced by that creature's mana value.) When you cast this spell, tap up to four target permanents.

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.

Whenever Fallowsage becomes tapped, you may draw a card.

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.

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

Trample Islandwalk (This creature can't be blocked as long as defending player controls an Island.) Shroud (This creature can't be the target of spells or abilities.)

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.

Kumena's Speaker gets +1/+1 as long as you control another Merfolk or an Island.

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

Whenever a spell or ability you control counters a spell, you may create a 1/1 blue Merfolk creature token. Tap seven untapped Merfolk you control: Counter target spell.

Changeling (This card is every creature type.) When Masked Vandal enters the battlefield, you may exile a creature card from your graveyard. If you do, exile target artifact or enchantment an opponent controls.

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

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.)

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.

Flash When Merfolk Trickster enters the battlefield, tap target creature an opponent controls. It loses all abilities until end of turn.

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.

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.

{U}: Counter target spell that targets Mistfolk.

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.

Changeling (This card is every creature type.) As Realmwalker enters the battlefield, choose a creature type. You may look at the top card of your library any time. You may cast creature spells of the chosen type from the top of your library.

When Reclamation Sage enters the battlefield, you may destroy target artifact or enchantment.

Islandwalk (This creature can't be blocked as long as defending player controls an Island.) {1}, {T}: Tap target land.

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

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

{3}, {T}: Search your library for a Merfolk permanent card, put it onto the battlefield, then shuffle.

Untap all permanents you control during each other player's untap step.

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.

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.

Islandwalk (This creature can't be blocked as long as defending player controls an Island.) All lands are Islands in addition to their other types. Creatures without flying or islandwalk can't attack.

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}.)

{T}: Target land becomes an Island until end of turn.

Kicker {1} (You may pay an additional {1} as you cast this spell.) When Tide Shaper enters the battlefield, if it was kicked, target land becomes an Island for as long as Tide Shaper remains on the battlefield. Tide Shaper gets +1/+1 as long as an opponent controls an Island.

As True-Name Nemesis enters the battlefield, choose a player. True-Name Nemesis has protection from the chosen player.

Flash Other Merfolk you control get +1/+1. Sacrifice a Merfolk: Counter target noncreature spell unless its controller pays {1}.

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

Whenever a creature you control attacks, you may put a quest counter on Beastmaster Ascension. As long as Beastmaster Ascension has seven or more quest counters on it, creatures you control get +5/+5.

Creatures you control have "{T}: Add one mana of any color."

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.)

Whenever a nontoken creature enters the battlefield under your control, if it doesn't have the same name as another creature you control or a creature card in your graveyard, 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.

Creatures don't untap during their controllers' untap steps. Whenever a creature enters the battlefield, untap all creatures.

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.

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

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}{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.

(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.

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.)

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.

Counter target spell. If that spell's mana value was 3 or less, proliferate. (Choose any number of permanents and/or players, then give each another counter of each kind already there.)

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

{T}: Add {C}. {G}{U}, {T}: You may cast spells this turn as though they had flash.

{T}: Add {G}. Channel — {1}{G}, Discard Boseiju, Who Endures: Destroy target artifact, enchantment, or nonbasic land an opponent controls. That player may search their library for a land card with a basic land type, put it onto the battlefield, then shuffle. This ability costs {1} less to activate for each legendary creature you control.

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

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

({T}: Add {U}.) Mystic Sanctuary enters the battlefield tapped unless you control three or more other Islands. When Mystic Sanctuary enters the battlefield untapped, you may put target instant or sorcery card from your graveyard on top of your library.

{T}: Add {C}. {G}{U}, {T}: Put a +1/+1 counter on each creature that entered the battlefield this turn.

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.

Choose a creature type. Draw a card for each permanent you control of that type.

Return all nonland permanents to their owners' hands. If you return four or more nontoken permanents you control this way, you may put a permanent card from your hand onto the battlefield.

As an additional cost to cast this spell, sacrifice a creature. Search your library for a creature card with mana value equal to 1 plus the sacrificed creature's mana value, put that card onto the battlefield with an additional +1/+1 counter on it, then shuffle.

Return all nonland permanents target player controls to their owner's hand.

Choose one — • Search your library for a basic land card, reveal it, put it into your hand, then shuffle. • Proliferate. (Choose any number of permanents and/or players, then give each another counter of each kind already there.)