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.

Equipped creature has "{T}: Add one mana of any color." Equip {1}

{T}: Add {C}{C}.

{T}, Tap an untapped creature you control: Add one mana of any color.

Instant and sorcery spells you cast cost {1} less to cast. Whenever a spell or ability you control counters a spell, you may draw a card. If you do, discard a card.

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

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.

Level up {1}{U} ({1}{U}: Put a level counter on this. Level up only as a sorcery.) LEVEL 1-2 0/1 {T}: Draw a card, then discard a card. LEVEL 3+ 0/1 {T}: Draw a card.

Whenever Grimoire Thief becomes tapped, exile the top three cards of target opponent's library face down. You may look at cards exiled with Grimoire Thief. {U}, Sacrifice Grimoire Thief: Turn all cards exiled with Grimoire Thief face up. Counter all spells with those names.

Whenever a Merfolk you control becomes tapped, you may gain 1 life.

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.

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.

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

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.

Tap an untapped Wizard you control: Counter target spell unless its controller pays {1}.

{W/U}, {Q}: Look at the top card of your library. You may exile that card. ({Q} is the untap symbol.)

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

When Spellseeker enters the battlefield, you may search your library for an instant or sorcery card with mana value 2 or less, reveal it, put it into your hand, then shuffle.

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.

Whenever Stonybrook Schoolmaster becomes tapped, you may create a 1/1 blue Merfolk Wizard creature token.

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.)

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.

Changeling (This card is every creature type.) Whenever you or a permanent you control becomes the target of a spell or ability an opponent controls, counter that spell or ability unless its controller pays {1}.

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

Whenever you draw a card, put a +1/+1 counter on each other Merfolk and/or Knight you control.

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.)

Commander creatures you own have "Whenever you cast a spell that shares a creature type with this creature, draw a card. This ability triggers only once each turn."

Enchant creature {U}: Tap enchanted creature. {U}: Untap enchanted creature.

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 upkeep, if an opponent controls more lands than you, you may search your library for up to three basic land cards, reveal them, put them into your hand, then shuffle.

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

Tap an untapped creature you control: Tap target artifact, creature, or land.

Whenever an opponent draws a card, that player may pay {2}. If the player doesn't, you create a Treasure token. (It's an artifact with "{T}, Sacrifice this artifact: Add one mana of any color.")

Enchant land When Spreading Seas enters the battlefield, draw a card. Enchanted land is an Island.

Choose one. If you control a commander as you cast this spell, you may choose both instead. • Creatures you control gain flying, vigilance, and double strike until end of turn. • Creatures you control gain lifelink, indestructible, and protection from all colors until end of turn.

Choose a creature type. Creatures you control of the chosen type get +1/+0 and gain indestructible until end of turn.

This spell can't be countered. Counter target noncreature spell.

Search your library for an artifact or enchantment card, reveal it, then shuffle and put that card on top.

If you control a commander, you may cast this spell without paying its mana cost. Counter target noncreature spell.

If you control a commander, you may cast this spell without paying its mana cost. Creatures you control gain indestructible until end of turn.

If it's not your turn, you may exile a blue card from your hand rather than pay this spell's mana cost. Counter target noncreature spell. If that spell is countered this way, exile it instead of putting it into its owner's graveyard.

Counter target instant or sorcery spell. Transmute {1}{U}{U} ({1}{U}{U}, Discard this card: Search your library for a card with the same mana value as this card, reveal it, put it into your hand, then shuffle. Transmute only as a sorcery.)

Counter target spell. At the beginning of your next upkeep, pay {3}{U}{U}. If you don't, you lose the game.

Exile target creature. Its controller may search their library for a basic land card, put that card onto the battlefield tapped, then shuffle.

Exile target creature. Its controller gains life equal to its power.

{T}: Add {C}. {T}: Add {W} or {U}. Adarkar Wastes deals 1 damage to you.

Boseiju, Who Shelters All enters the battlefield tapped. {T}, Pay 2 life: Add {C}. If that mana is spent on an instant or sorcery spell, that spell can't be countered.

{T}: Add one mana of any color in your commander's color identity.

{T}, Sacrifice Evolving Wilds: Search your library for a basic land card, put it onto the battlefield tapped, then shuffle.

Glacial Fortress enters the battlefield tapped unless you control a Plains or an Island. {T}: Add {W} or {U}.

{T}: Add {C}. ({C} represents colorless mana.) {T}, Tap an untapped creature you control: Add one mana of any color.

({T}: Add {W} or {U}.) Irrigated Farmland enters the battlefield tapped. Cycling {2} ({2}, Discard this card: Draw a card.)

({T}: Add {U}.)

{T}: Add {C}. {W/U}, {T}: Add {W}{W}, {W}{U}, or {U}{U}.

({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.

Path of Ancestry enters the battlefield tapped. {T}: Add one mana of any color in your commander's color identity. When that mana is spent to cast a creature spell that shares a creature type with your commander, scry 1. (Look at the top card of your library. You may put that card on the bottom.)

({T}: Add {W}.)

As Port Town enters the battlefield, you may reveal a Plains or Island card from your hand. If you don't, Port Town enters the battlefield tapped. {T}: Add {W} or {U}.

({T}: Add {W} or {U}.) Prairie Stream enters the battlefield tapped unless you control two or more basic lands.

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

{T}: Add {C}. {1}{U}, {T}: Return target Wizard you control to its owner's hand.

Sea of Clouds enters the battlefield tapped unless you have two or more opponents. {T}: Add {W} or {U}.

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.

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

{T}: Add {C}. {T}, Tap an untapped creature you control: Add one mana of any color.

{T}, Sacrifice Terramorphic Expanse: Search your library for a basic land card, put it onto the battlefield tapped, then shuffle.

As Unclaimed Territory 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.

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.

Search your library for an enchantment card, reveal it, put it into your hand, then shuffle.

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

Search your library for an Equipment card, reveal that card, put it into your hand, then shuffle.

Create two 1/1 blue Merfolk Wizard creature tokens. Tap four untapped Merfolk you control: Return Summon the School from your graveyard to your hand.

At the beginning of your upkeep, you may put a charge counter on Aether Vial. {T}: You may put a creature card with mana value equal to the number of charge counters on Aether Vial from your hand onto the battlefield.

Tap two untapped Wizards you control: Tap target permanent.

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.

{T}: Add one mana of any color in your commander's color identity.

Flying, ward {2} Whenever you cast a Faerie or Wizard permanent spell, copy it. (The copy becomes a token.)

Tap an untapped Wizard you control: Draw a card.

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

Whenever a creature enters the battlefield under your control, put a +1/+1 counter on each creature you control.

{T}: Add one mana of any color in your commander's color identity. Sacrifice Commander's Sphere: Draw a card.

Equipped creature gets +1/+1 and has vigilance. Whenever equipped creature attacks, look at the top six cards of your library. You may reveal a card that shares a creature type with that creature from among them and put it into your hand. Put the rest on the bottom of your library in a random order. Equip {1}

Counter target spell.

Tap two untapped creatures you control: You may put a creature card from your hand that shares a creature type with each creature tapped this way onto the battlefield.

{T}: Add one mana of any color. Crew 3 (Tap any number of creatures you control with total power 3 or more: This Vehicle becomes an artifact creature until end of turn.)

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

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.

({W/U} can be paid with either {W} or {U}.) Whenever a player casts a noncreature spell, counter that spell. That player creates X 1/1 white and blue Bird creature tokens with flying, where X is the spell's mana value.

Landfall — Whenever a land enters the battlefield under your control, choose one — • Create a 2/2 white Cat Beast creature token. • Put a +1/+1 counter on each creature you control. Those creatures gain vigilance until end of turn.

{T}: Add one mana of any color that a land an opponent controls could produce.

You may pay 1 life and exile a blue card from your hand rather than pay this spell's mana cost. Counter target spell.

Tap an untapped Wizard you control: Return target nonland permanent you don't control to its owner's hand.

Flying {U}, Sacrifice Glen Elendra Archmage: Counter target noncreature spell. Persist (When this creature dies, if it had no -1/-1 counters on it, return it to the battlefield under its owner's control with a -1/-1 counter on it.)

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.

Counter target spell that targets you or a permanent you control. Draw a card.

As Icon of Ancestry enters the battlefield, choose a creature type. Creatures you control of the chosen type get +1/+1. {3}, {T}: Look at the top three cards of your library. You may reveal a creature card of the chosen type from among them and put it into your hand. Put the rest on the bottom of your library in a random order.

Counter target spell. At the beginning of your next main phase, add an amount of {C} equal to that spell's mana value.

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

Changeling (This card is every creature type.) {X}: Until end of turn, creatures you control have base power and toughness X/X and gain all creature types.

Each other creature becomes a copy of target nonlegendary creature until end of turn.

Cumulative upkeep {1} (At the beginning of your upkeep, put an age counter on this permanent, then sacrifice it unless you pay its upkeep cost for each age counter on it.) Whenever an opponent casts a noncreature spell, you may draw a card unless that player pays {4}.

Enchant creature {U}: Untap enchanted creature. {U}: Enchanted creature gains flying until end of turn. {U}: Enchanted creature gains shroud until end of turn. (It can't be the target of spells or abilities.) {1}: Enchanted creature gets +1/-1 or -1/+1 until end of turn.

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

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 can't cast spells this turn.

Whenever an opponent casts a spell, you may draw a card unless that player pays {1}.

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

Kicker {5} (You may pay an additional {5} as you cast this spell.) Create a token that's a copy of target creature. If this spell was kicked, create five of those tokens instead.

Each other Wizard creature you control enters the battlefield with an additional +1/+1 counter on it. {2}, Remove a +1/+1 counter from a creature you control: Draw a card.

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

When Sharae of Numbing Depths enters the battlefield, tap target creature an opponent controls and put a stun counter on it. (If a permanent with a stun counter would become untapped, remove one from it instead.) Whenever you tap one or more untapped creatures your opponents control, draw a card. This ability triggers only once each turn.

{1}{U}, Tap two untapped Wizards you control: Copy target instant or sorcery spell. You may choose new targets for the copy.

As an additional cost to cast this spell, reveal a Merfolk card from your hand or pay {3}. When Silvergill Adept enters the battlefield, draw a card.

Choose one or more — • Counter target spell. • Counter target activated or triggered ability. • Return target nonland permanent to its owner's hand. • Create a token that's a copy of target creature you control. • Target player draws a card.

Counter target enchantment, instant, or sorcery spell. Its controller creates a 2/2 blue Bird creature token with flying.

{T}: Add {C}. {T}: Add {W} or {U}. Talisman of Progress deals 1 damage to you.

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

Flash (You may cast this spell any time you could cast an instant.) When Vedalken Aethermage enters the battlefield, return target Sliver to its owner's hand. Wizardcycling {3} ({3}, Discard this card: Search your library for a Wizard card, reveal it, put it into your hand, then shuffle.)

Wand of the Worldsoul enters the battlefield tapped. {T}: Add {W}. {T}: The next spell you cast this turn has convoke.