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 Caged Sun enters the battlefield, choose a color. Creatures you control of the chosen color get +1/+1. Whenever a land's ability causes you to add one or more mana of the chosen color, add one additional mana of that color.

Each creature gets +1/+1 for each other creature on the battlefield that shares at least one creature type with it. (For example, if two Goblin Warriors and a Goblin Shaman are on the battlefield, each gets +2/+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.

Creatures you control get +1/+1 and have flying and indestructible. At the beginning of your upkeep, sacrifice a creature. If you can't, sacrifice Eldrazi Monument.

Whenever equipped creature attacks, look at the top card of your library. If it's a land card, you may put it onto the battlefield tapped. Equip {1} ({1}: Attach to target creature you control. Equip only as a sorcery.)

As Heraldic Banner enters the battlefield, choose a color. Creatures you control of the chosen color get +1/+0. {T}: Add one mana of the chosen color.

{T}: Add {U}. {2}{U}: Put an hour counter on Midnight Clock. At the beginning of each upkeep, put an hour counter on Midnight Clock. When the twelfth hour counter is put on Midnight Clock, shuffle your hand and graveyard into your library, then draw seven cards. Exile Midnight Clock.

Convoke (Your creatures can help cast this spell. Each creature you tap while casting this spell pays for {1} or one mana of that creature's color.) As Obelisk of Urd enters the battlefield, choose a creature type. Creatures you control of the chosen type get +2/+2.

As Adaptive Automaton enters the battlefield, choose a creature type. Adaptive Automaton is the chosen type in addition to its other types. Other creatures you control of the chosen type get +1/+1.

{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.

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

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

Level up {1} ({1}: Put a level counter on this. Level up only as a sorcery.) LEVEL 2-3 3/3 Flying LEVEL 4+ 4/4 Flying Other Merfolk creatures you control get +1/+1.

Whenever an opponent shuffles their library, you may put a +1/+1 counter on Cosi's Trickster.

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.

{U}: Return Darting Merfolk to its owner's hand.

Flying As an additional cost to cast blue permanent spells, you may pay 2 life. Those spells cost {U} less to cast if you paid life this way. This effect reduces only the amount of blue mana you pay. Whenever you cast a blue permanent spell, draw a card.

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

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.

You may cast Harbinger of the Tides as though it had flash if you pay {2} more to cast it. (You may cast it any time you could cast an instant.) When Harbinger of the Tides enters the battlefield, you may return target tapped creature an opponent controls to its owner's hand.

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.

Whenever Library Larcenist attacks, draw a card.

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

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

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

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.

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.

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.

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

{T}: Target land becomes the basic land type of your choice until end of turn.

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.

{T}, Sacrifice Rootwater Diver: Return target artifact card from your graveyard to your hand.

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

{T}: Target creature gets -X/-0 until end of turn, where X is the number of Merfolk and/or Faeries you control.

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.

{T}: Target Merfolk creature gets +1/+1 and gains islandwalk until end of turn. (It can't be blocked as long as defending player controls an Island.) {T}: Target land becomes an Island until end of turn.

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}.)

When Thassa's Oracle enters the battlefield, look at the top X cards of your library, where X is your devotion to blue. Put up to one of them on top of your library and the rest on the bottom of your library in a random order. If X is greater than or equal to the number of cards in your library, you win the game. (Each {U} in the mana costs of permanents you control counts toward your devotion to blue.)

{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.

{T}: Target land becomes the basic land type of your choice until end of turn. Activate only during your turn.

Triton Shorestalker can't be blocked.

Other blue creatures you control have "Whenever this creature becomes tapped, draw a card, then discard a card." Other artifact creatures you control get +1/+1. {U/P}: Until end of turn, target creature you control becomes a blue artifact in addition to its other colors and types. Activate only as a sorcery. ({U/P} can be paid with either {U} or 2 life.)

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

When Court of Vantress enters the battlefield, you become the monarch. At the beginning of your upkeep, choose up to one other target enchantment or artifact. If you're the monarch, you may create a token that's a copy of it. If you're not the monarch, you may have Court of Vantress become a copy of it, except it has this ability.

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.)

Enchant creature When Infinite Reflection enters the battlefield attached to a creature, each other nontoken creature you control becomes a copy of that creature. Nontoken creatures you control enter the battlefield as a copy of enchanted creature.

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.)

Counter target spell. Its controller may draw up to two cards at the beginning of the next turn's upkeep. You draw a card at the beginning of the next turn's upkeep.

Target player draws X cards. Shuffle Blue Sun's Zenith into its owner's library.

{T}: Add {C}. {T}, Sacrifice Ghost Quarter: Destroy target land. Its controller may search their library for a basic land card, put it onto the battlefield, then shuffle.

({T}: Add {U}.)

Mirrorpool enters the battlefield tapped. {T}: Add {C}. {2}{C}, {T}, Sacrifice Mirrorpool: Copy target instant or sorcery spell you control. You may choose new targets for the copy. {4}{C}, {T}, Sacrifice Mirrorpool: Create a token that's a copy of target creature you control.

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.