Merfolk Windrobber

Flying
Whenever Merfolk Windrobber deals combat damage to a player, that player mills a card. (They put the top card of their library into their graveyard.)
Sacrifice Merfolk Windrobber: Draw a card. Activate only if an opponent has eight or more cards in their graveyard.

Lullmage's Domination

This spell costs {3} less to cast if it targets a creature whose controller has eight or more cards in their graveyard.
Gain control of target creature with mana value X.

Merrow Reejerey

Other Merfolk creatures you control get +1/+1.
Whenever you cast a Merfolk spell, you may tap or untap target permanent.

One With the Wind

Enchant creature
Enchanted creature gets +2/+2 and has flying.

Triton Shorestalker

Furtive Courier

Furtive Courier can't be blocked as long as you've sacrificed an artifact this turn.
Whenever Furtive Courier attacks, draw a card, then discard a card.

River Sneak

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

Many Partings

Search your library for a basic land card, reveal it, put it into your hand, then shuffle. Create a Food token. (It's an artifact with "{2}, {T}, Sacrifice this artifact: You gain 3 life.")

Kiora, Behemoth Beckoner

Whenever a creature with power 4 or greater enters the battlefield under your control, draw a card.
−1: Untap target permanent.

Eureka Moment

Draw two cards. You may put a land card from your hand onto the battlefield.

Library Larcenist

Whenever Library Larcenist attacks, draw a card.

Awakened Skyclave

Vigilance, haste
As long as Awakened Skyclave is on the battlefield, it's a land in addition to its other types.
{T}: Add one mana of any color.

Invasion of Zendikar

(As a Siege enters, choose an opponent to protect it. You and others can attack it. When it's defeated, exile it, then cast it transformed.)
When Invasion of Zendikar enters the battlefield, search your library for up to two basic land cards, put them onto the battlefield tapped, then shuffle.

Invasion of Zendikar // Awakened Skyclave

Adventure Awaits

Look at the top five 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 a random order. If you didn't put a card into your hand this way, draw a card.

Aquatic Incursion

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.

Commune with Nature

Look at the top five 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.

A Killer Among Us

When A Killer Among Us enters the battlefield, create a 1/1 white Human creature token, a 1/1 blue Merfolk creature token, and a 1/1 red Goblin creature token. Then secretly choose Human, Merfolk, or Goblin.
Sacrifice A Killer Among Us, Reveal the creature type you chose: If target attacking creature token is the chosen type, put three +1/+1 counters on it and it gains deathtouch until end of turn.

Tamiyo's Compleation

Flash
Enchant artifact, creature, or planeswalker
When Tamiyo's Compleation enters the battlefield, tap enchanted permanent. If it's an Equipment, unattach it.
Enchanted permanent loses all abilities and doesn't untap during its controller's untap step.

Tatyova, Steward of Tides

Land creatures you control have flying.
Whenever a land enters the battlefield under your control, if you control seven or more lands, up to one target land you control becomes a 3/3 Elemental creature with haste. It's still a land.

Druid Class

(Gain the next level as a sorcery to add its ability.)
Landfall — Whenever a land enters the battlefield under your control, you gain 1 life.
{2}{G}: Level 2
You may play an additional land on each of your turns.
{4}{G}: Level 3
When this Class becomes level 3, target land you control becomes a creature with haste and "This creature's power and toughness are each equal to the number of lands you control." It's still a land.

Shore Up

Target creature you control gets +1/+1 and gains hexproof until end of turn. Untap it. (It can't be the target of spells or abilities your opponents control.)

Secluded Courtyard

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.

The Surgical Bay

The Surgical Bay enters the battlefield tapped.
{T}: Add {U}.
{1}{U}, {T}, Sacrifice The Surgical Bay: Draw a card.

Sol Ring

Commune with Spirits

Look at the top four cards of your library. You may reveal an enchantment or land card from among them and put it into your hand. Put the rest on the bottom of your library in a random order.

Tangled Islet

({T}: Add {G} or {U}.)
Tangled Islet enters the battlefield tapped.

Tazeem Roilmage

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.

Skyclave Invader

Flying
When this creature transforms into Skyclave Invader, look at the top card of your library. If it's a land card, you may put it onto the battlefield. If you don't put the card onto the battlefield, put it into your hand.

Skyclave Aerialist

Flying
{4}{G/P}: Transform Skyclave Aerialist. Activate only as a sorcery. ({G/P} can be paid with either {G} or 2 life.)

Skyclave Aerialist // Skyclave Invader

The Hunter Maze

The Hunter Maze enters the battlefield tapped.
{T}: Add {G}.
{1}{G}, {T}, Sacrifice The Hunter Maze: Draw a card.

Windrider Patrol

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.)

Thriving Isle

Thriving Isle enters the battlefield tapped.
As Thriving Isle enters the battlefield, choose a color other than blue.
{T}: Add {U} or one mana of the chosen color.

Long List of the Ents

(As this Saga enters and after your draw step, add a lore counter. Sacrifice after VI.)
I, II, III, IV, V, VI — Note a creature type that hasn't been noted for Long List of the Ents. When you next cast a creature spell of that type this turn, that creature enters the battlefield with an additional +1/+1 counter on it.

Thirsting Roots

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.)

Forest

Kiora, the Crashing Wave

+1: Until your next turn, prevent all damage that would be dealt to and dealt by target permanent an opponent controls.
−1: Draw a card. You may play an additional land this turn.
−5: You get an emblem with "At the beginning of your end step, create a 9/9 blue Kraken creature token."

Evidence Examiner

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.")

Vivisurgeon's Insight

Draw three cards. Proliferate. (Choose any number of permanents and/or players, then give each another counter of each kind already there.)

Benthic Criminologists

Whenever Benthic Criminologists enters the battlefield or attacks, you may sacrifice an artifact. If you do, draw a card.

Kami of Whispered Hopes

If one or more +1/+1 counters would be put on a permanent you control, that many plus one +1/+1 counters are put on that permanent instead.
{T}: Add X mana of any one color, where X is Kami of Whispered Hopes's power.

Expand the Sphere

Look at the top six cards of your library. Put up to two land cards from among them onto the battlefield tapped and the rest on the bottom of your library in a random order. If you put fewer than two lands onto the battlefield this way, proliferate a number of times equal to the difference. (Choose any number of permanents and/or players, then give each another counter of each kind already there.)

Stasis Field

Enchant creature
Enchanted creature has base power and toughness 0/2, has defender, and loses all other abilities.

Vineglimmer Snarl

As Vineglimmer Snarl enters the battlefield, you may reveal a Forest or Island card from your hand. If you don't, Vineglimmer Snarl enters the battlefield tapped.
{T}: Add {G} or {U}.

Quandrix Campus

Quandrix Campus enters the battlefield tapped.
{T}: Add {G} or {U}.
{4}, {T}: Scry 1.

Cenote Scout

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.)

Quandrix Pledgemage

Magecraft — Whenever you cast or copy an instant or sorcery spell, put a +1/+1 counter on Quandrix Pledgemage.

Get a Leg Up

Until end of turn, target creature gets +1/+1 for each creature you control and gains reach.

Saltwater Stalwart

Whenever Saltwater Stalwart deals damage to an opponent, target player draws a card.

Filter Out

Return all noncreature, nonland permanents to their owners' hands.

Soothsayer Adept

{1}{U}, {T}: Draw a card, then discard a card.

Merfolk Sovereign

Other Merfolk creatures you control get +1/+1.
{T}: Target Merfolk creature can't be blocked this turn.

Tatyova, Benthic Druid

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

Hakbal of the Surging Soul

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.

Crashing Tide

This spell has flash as long as you control a Merfolk.
Return target creature to its owner's hand.
Draw a card.

Island

Nissa, Worldwaker

+1: Target land you control becomes a 4/4 Elemental creature with trample. It's still a land.
+1: Untap up to four target Forests.
−7: Search your library for any number of basic land cards, put them onto the battlefield, then shuffle. Those lands become 4/4 Elemental creatures with trample. They're still lands.

Merfolk Mistbinder

Snap

Return target creature to its owner's hand. Untap up to two lands.

Kasmina, Enigma Sage

Each other planeswalker you control has the loyalty abilities of Kasmina, Enigma Sage.
+2: Scry 1.
−X: Create a 0/0 green and blue Fractal creature token. Put X +1/+1 counters on it.
−8: Search your library for an instant or sorcery card that shares a color with this planeswalker, exile that card, then shuffle. You may cast that card without paying its mana cost.

Scale the Heights

Put a +1/+1 counter on up to one target creature. You gain 2 life. You may play an additional land this turn.
Draw a card.

Nicanzil, Current Conductor

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.

Expedition Lookout

Defender
As long as an opponent has eight or more cards in their graveyard, Expedition Lookout can attack as though it didn't have defender and it can't be blocked.

Merfolk Falconer

Flying
Whenever you cast a kicked spell, scry 2.

Moss Diamond

Moss Diamond enters the battlefield tapped.
{T}: Add {G}.

You Come to a River

Choose one —
• Fight the Current — Return target nonland permanent to its owner's hand.
• Find a Crossing — Target creature gets +1/+0 until end of turn and can't be blocked this turn.

Adventurous Impulse

Look at the top three cards of your library. You may reveal a creature or land card from among them and put it into your hand. Put the rest on the bottom of your library in any order.

Negate

Solve the Equation

Search your library for an instant or sorcery card, reveal it, put it into your hand, then shuffle.

Thornwood Falls

Thornwood Falls enters the battlefield tapped.
When Thornwood Falls enters the battlefield, you gain 1 life.
{T}: Add {G} or {U}.

Branch of Boseiju

Reach
Branch of Boseiju gets +1/+1 for each land you control.

Boseiju Reaches Skyward

(As this Saga enters and after your draw step, add a lore counter.)
I — Search your library for up to two basic Forest cards, reveal them, put them into your hand, then shuffle.
II — Put up to one target land card from your graveyard on top of your library.
III — Exile this Saga, then return it to the battlefield transformed under your control.

Boseiju Reaches Skyward // Branch of Boseiju

Ephara's Dispersal

This spell costs {2} less to cast if it targets an attacking creature.
Return target creature to its owner's hand. Surveil 2. (Look at the top two cards of your library, then put any number of them into your graveyard and the rest on top of your library in any order.)

Seafloor Stalker

{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.)

March of Swirling Mist

As an additional cost to cast this spell, you may exile any number of blue cards from your hand. This spell costs {2} less to cast for each card exiled this way.
Up to X target creatures phase out. (While they're phased out, they're treated as though they don't exist. Each one phases in before its controller untaps during their next untap step.)

Cascade Seer

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.)

Golden Ratio

Draw a card for each different power among creatures you control.

Cleric of Chill Depths

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

Thought Vessel

You have no maximum hand size.
{T}: Add {C}.

They Went This Way

Search your library for a basic land card, put it onto the battlefield tapped, then shuffle. Investigate. (Create a Clue token. It's an artifact with "{2}, Sacrifice this artifact: Draw a card.")

Watertrap Weaver

When Watertrap Weaver enters the battlefield, tap target creature an opponent controls. That creature doesn't untap during its controller's next untap step.

Mistway Spy

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.