{U}, Sacrifice Aether Spellbomb: Return target creature to its owner's hand. {1}, Sacrifice Aether Spellbomb: Draw a card.

Equipped creature gets +1/+1 for each charge counter on Banshee's Blade. Whenever equipped creature deals combat damage, put a charge counter on Banshee's Blade. Equip {2} ({2}: Attach to target creature you control. Equip only as a sorcery. This card enters the battlefield unattached and stays on the battlefield if the creature leaves.)

Equipped creature has base power and toughness 10/10. Equip {10}. This ability costs {X} less to activate, where X is the power of the creature it targets.

Equipped creature gets +1/+0 and has wither. (It deals damage to creatures in the form of -1/-1 counters.) Equip {2}

As Door of Destinies enters the battlefield, choose a creature type. Whenever you cast a spell of the chosen type, put a charge counter on Door of Destinies. Creatures you control of the chosen type get +1/+1 for each charge counter on Door of Destinies.

Whenever Hammer of Nazahn or another Equipment enters the battlefield under your control, you may attach that Equipment to target creature you control. Equipped creature gets +2/+0 and has indestructible. Equip {4}

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.)

Equipped creature has first strike and "{T}, Unattach Surestrike Trident: This creature deals damage equal to its power to target player or planeswalker." Equip {4} ({4}: Attach to target creature you control. Equip only as a sorcery. This card enters the battlefield unattached and stays on the battlefield if the creature leaves.)

Kicker—Return a creature you control to its owner's hand. (You may return a creature you control to its owner's hand in addition to any other costs as you cast this spell.) If Arctic Merfolk was kicked, it enters the battlefield with a +1/+1 counter on it.

{1}{U}: Adapt 1. (If this creature has no +1/+1 counters on it, put a +1/+1 counter on it.) Whenever one or more +1/+1 counters are put on Benthic Biomancer, draw a card, then discard a card.

Flash (You may cast this spell any time you could cast an instant.) Whenever you cast a spell during an opponent's turn, put a +1/+1 counter on Brineborn Cutthroat.

{1}{U}, {T}: Target creature gains flying until end of turn.

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.)

{1}{G}, {T}: This turn, each creature you control enters the battlefield with an additional +1/+1 counter on it. {1}{U}, {T}: Move a +1/+1 counter from target creature you control onto another target creature you control.

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

{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.

Blue creatures you control can't be blocked.

{U}: Deeptread Merrow gains islandwalk until end of turn. (It can't be blocked as long as defending player controls an Island.)

Inspired — Whenever Deepwater Hypnotist becomes untapped, target creature an opponent controls gets -3/-0 until end of turn.

Whenever a player casts a blue spell, you may pay {1}. If you do, target player mills two cards.

Tap an untapped Merfolk you control: Target player mills a card.

Whenever Fallowsage becomes tapped, you may draw a card.

Flying

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

{U}: Manta Riders gains flying until end of turn.

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

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.)

When Merrow Witsniper enters the battlefield, target player mills a card.

Sacrifice Mistcaller: Until end of turn, if a nontoken creature would enter the battlefield and it wasn't cast, exile it instead.

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

Cycling {2} ({2}, Discard this card: Draw a card.)

{T}: Add {C}. {1}, {T}: Add {U}.

{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.)

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

Enchant creature Enchanted creature has flying. Threshold — Enchanted creature has shroud as long as seven or more cards are in your graveyard. (It can't be the target of spells or abilities.)

Enchant creature Enchanted creature gets +1/+0 and can't be blocked.

Enchant creature Enchanted creature can't be the target of spells and can't be enchanted by other Auras.

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.

Whenever one or more nontoken Merfolk you control become tapped, create a 1/1 blue Merfolk creature token with hexproof.

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.)

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.

As Reflections of Littjara enters the battlefield, choose a creature type. Whenever you cast a spell of the chosen type, copy that spell. (A copy of a permanent spell becomes a token.)

As an additional cost to cast this spell, sacrifice a blue permanent. Counter target spell.

Raid — If you attacked this turn, you may pay {U} rather than pay this spell's mana cost. Counter target spell.

Counter target instant or Aura spell that targets a permanent you control.

Choose one — • Counter target red spell. • Destroy target red permanent.

Counter target spell. You may cast a spell that shares a card type with it from your hand without paying its mana cost.

Counter target spell. Its controller mills four cards.

Counter target spell.

Counter target instant spell.

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

{T}: Add {C}. {1}, {T}: Until end of turn, creatures your opponents control lose hexproof and shroud and can't have hexproof or shroud.

{T}: Add {C}. {T}, Sacrifice Archaeological Dig: Add one mana of any color.

Botanical Sanctum enters the battlefield tapped unless you control two or fewer other lands. {T}: Add {G} or {U}.

({T}: Add {G} or {U}.) As Breeding Pool enters the battlefield, you may pay 2 life. If you don't, it enters the battlefield tapped.

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

Desert of the Indomitable enters the battlefield tapped. {T}: Add {G}. Cycling {1}{G} ({1}{G}, Discard this card: Draw a card.)

Desert of the Mindful enters the battlefield tapped. {T}: Add {U}. Cycling {1}{U} ({1}{U}, Discard this card: Draw a card.)

{T}: Add {C}. {2}, {T}: Put two +1/+1 counters on target non-Human creature that entered the battlefield this turn.

Faerie Conclave enters the battlefield tapped. {T}: Add {U}. {1}{U}: Faerie Conclave becomes a 2/1 blue Faerie creature with flying until end of turn. It's still a land.

({T}: Add {G}.)

{T}: Add {C}. {2}, {T}: Each player draws a card, then discards a card.

If you control two or more other lands, Hall of Storm Giants enters the battlefield tapped. {T}: Add {U}. {5}{U}: Until end of turn, Hall of Storm Giants becomes a 7/7 blue Giant creature with ward {3}. It's still a land. (Whenever it becomes the target of a spell or ability an opponent controls, counter it unless that player pays {3}.)

Hidden Cataract enters the battlefield tapped. {T}: Add {U}. {4}{U}, {T}, Sacrifice Hidden Cataract: Discover 4. Activate only as a sorcery. (Exile cards from the top of your library until you exile a nonland card with mana value 4 or less. Cast it without paying its mana cost or put it into your hand. Put the rest on the bottom in a random order.)

({T}: Add {U}.)

{T}, Pay 1 life, Sacrifice Misty Rainforest: Search your library for a Forest or Island card, put it onto the battlefield, then shuffle.

Skyshroud Forest enters the battlefield tapped. {T}: Add {C}. {T}: Add {G} or {U}. Skyshroud Forest deals 1 damage to you.

Target creature can't be blocked this turn. Flashback {U} (You may cast this card from your graveyard for its flashback cost. Then exile it.)