Learn. (You may reveal a Lesson card you own from outside the game and put it into your hand, or discard a card to draw a card.)
{2}{U}
Bewilder
Instant
Target creature gets -3/-0 until end of turn.
Draw a card.
{1}{G}
Big Play
Instant
Target creature gets +2/+2 and gains reach until end of turn. Put a +1/+1 counter on it.
{2}{G}
Blinding Fog
Instant
Prevent all damage that would be dealt to creatures this turn. Creatures you control gain hexproof until end of turn. (They can't be the targets of spells or abilities your opponents control.)
{1}{G}
Bramble Armor
Artifact - Equipment
When Bramble Armor enters the battlefield, attach it to target creature you control.
Equipped creature gets +2/+1.
Equip {4} ({4}: Attach to target creature you control. Equip only as a sorcery.)
{1}{G}
Deeproot Warrior
Creature - Merfolk Warrior
Whenever Deeproot Warrior becomes blocked, it gets +1/+1 until end of turn.
2 /
2
{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.)
{U}
Dive Down
Instant
Target creature you control gets +0/+3 and gains hexproof until end of turn. (It can't be the target of spells or abilities your opponents control.)
{G}{U}
Double Major
Instant
Copy target creature spell you control, except it isn't legendary if the spell is legendary. (A copy of a creature spell becomes a token.)
{2}{U}
Emry, Lurker of the Loch
Legendary Creature - Merfolk Wizard
This spell costs {1} less to cast for each artifact you control.
When Emry, Lurker of the Loch enters the battlefield, mill four cards.
{T}: Choose target artifact card in your graveyard. You may cast that card this turn. (You still pay its costs. Timing rules still apply.)
1 /
2
{X}{X}{G}{G}
Exponential Growth
Sorcery
Until end of turn, double target creature's power X times.
{3}{U}
Headwater Sentries
Creature - Merfolk Warrior
2 /
5
{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}
Lucky Clover
Artifact
Whenever you cast an Adventure instant or sorcery spell, copy it. You may choose new targets for the copy.
{U}
Mantle of Tides
Artifact - Equipment
Equipped creature gets +1/+2.
Whenever you draw your second card each turn, attach Mantle of Tides to target creature you control.
Equip {3} ({3}: Attach to target creature you control. Equip only as a sorcery.)
{U}{ // }{U}
Merfolk Secretkeeper // Venture Deeper
Creature - Merfolk Wizard // Sorcery - Adventure
Target player mills four cards. (Then exile this card. You may cast the creature later from exile.)
0 /
4
{5}{U}
Moonlit Scavengers
Creature - Merfolk Rogue
When Moonlit Scavengers enters the battlefield, if you control an artifact or enchantment, return target creature an opponent controls to its owner's hand.
4 /
5
{1}{U}
Negate
Instant
Counter target noncreature spell.
{2}{G}
New Horizons
Enchantment - Aura
Enchant land
When New Horizons enters the battlefield, put a +1/+1 counter on target creature you control.
Enchanted land has "{T}: Add two mana of any one color."
{1}{U}
One With the Wind
Enchantment - Aura
Enchant creature
Enchanted creature gets +2/+2 and has flying.
{1}{U}
Reject
Instant
Counter target creature or planeswalker spell unless its controller pays {3}. If that spell is countered this way, exile it instead of putting it into its owner's graveyard.
{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.
{4}{U}
Sage of the Falls
Creature - Merfolk Wizard
Whenever Sage of the Falls or another non-Human creature enters the battlefield under your control, you may draw a card. If you do, discard a card.
2 /
5
{1}{U}
Search for Azcanta
Legendary Enchantment
At the beginning of your upkeep, surveil 1. Then if you have seven or more cards in your graveyard, you may transform Search for Azcanta. (Look at the top card of your library. You may put that card into your graveyard.)
--
Azcanta, the Sunken Ruin
Legendary Land
(Transforms from Search for Azcanta.)
{T}: Add {U}.
{2}{U}, {T}: Look at the top four cards of your library. You may reveal a noncreature, nonland card from among them and put it into your hand. Put the rest on the bottom of your library in any order.
{1}{U}
Shaper Apprentice
Creature - Merfolk Wizard
Shaper Apprentice has flying as long as you control another Merfolk.
2 /
1
{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
{G}
Shapers' Sanctuary
Enchantment
Whenever a creature you control becomes the target of a spell or ability an opponent controls, you may draw a card.
{1}{U}
Soothsayer Adept
Creature - Merfolk Wizard
{1}{U}, {T}: Draw a card, then discard a card.
1 /
3
{1}{G/U}
Square Up
Instant
Target creature has base power and toughness 4/4 until end of turn.
{3}{U}
Storm Sculptor
Creature - Merfolk Wizard
Storm Sculptor can't be blocked.
When Storm Sculptor enters the battlefield, return a creature you control to its owner's hand.
3 /
2
{2}{U}{U}
Tempest Caller
Creature - Merfolk Wizard
When Tempest Caller enters the battlefield, tap all creatures target opponent controls.
2 /
3
{2}{G}
Tishana's Wayfinder
Creature - Merfolk Scout
When Tishana's Wayfinder 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 /
2
{2}{G}{G}
Waker of the Wilds
Creature - Merfolk Shaman
{X}{G}{G}: Put X +1/+1 counters on target land you control. That land becomes a 0/0 Elemental creature with haste. It's still a land.
3 /
3
{2}{U}
Watertrap Weaver
Creature - Merfolk Wizard
When Watertrap Weaver enters the battlefield, tap target creature an opponent controls. That creature doesn't untap during its controller's next untap step.
2 /
2
{4}{U}
Wind Strider
Creature - Merfolk Wizard
Flash
Flying
3 /
3
{1}{U}
Wishful Merfolk
Creature - Merfolk
Defender
{1}{U}: Wishful Merfolk loses defender and becomes a Human until end of turn.