Creatures you control with +1/+1 counters on them can't be blocked.

Counter target spell that targets a creature. Draw a card.

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.

You may exile a blue card from your hand rather than pay this spell's mana cost. Change the target of target spell with a single target.

Surge {U}{U} (You may cast this spell for its surge cost if you or a teammate has cast another spell this turn.) This spell can't be countered. Counter target spell.

Proliferate, then choose any number of permanents you control that had a counter put on them this way. Those permanents phase out. (To proliferate, choose any number of permanents and/or players, then give each another counter of each kind already there. Treat phased-out permanents and anything attached to them as though they don't exist until their controller's next turn.)

Flash When this creature enters, put a shield counter on another target creature you control. (If it would be dealt damage or destroyed, remove a shield counter from it instead.) You may cast Merfolk spells as though they had flash.

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

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

{T}: Untap another target permanent.

Search your library for up to two basic land cards, reveal those cards, put one onto the battlefield tapped and the other into your hand, then shuffle.

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.

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

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.)

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.

If one or more +1/+1 counters would be put on a creature you control, twice that many +1/+1 counters are put on that creature instead.

Whenever another Merfolk you control enters, put a +1/+1 counter on target Merfolk you control.

If one or more +1/+1 counters would be put on a creature you control, that many plus one +1/+1 counters are put on it instead.

As this creature enters, choose a creature type. This creature is the chosen type in addition to its other types. Each other creature you control of the chosen type enters with an additional +1/+1 counter on it.

{1}{G}{U}: Put a +1/+1 counter on target creature you control. Whenever one or more +1/+1 counters are put on a creature you control, put that many growth counters on this enchantment. At the beginning of your upkeep, if this enchantment has twenty or more growth counters on it, you win the game.

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

This land enters tapped unless you control two or fewer other lands. {T}: Add {G} or {U}.

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

({T}: Add {G}.)

This land enters tapped unless you control a Forest or an Island. {T}: Add {G} or {U}.

({T}: Add {U}.)

{T}: Add {C}. {4}, {T}: Proliferate. (Choose any number of permanents and/or players, then give each another counter of each kind already there.)

This land enters tapped. {T}: Add {G}. Graft 1 (This land enters with a +1/+1 counter on it. Whenever a creature enters, you may move a +1/+1 counter from this land onto it.)

Hideaway 4 (When this land enters, look at the top four cards of your library, exile one face down, then put the rest on the bottom in a random order.) This land enters tapped. {T}: Add {G}. {G}, {T}: You may play the exiled card without paying its mana cost if creatures you control have total power 10 or greater.

This land enters tapped. {T}: Add {C}. {2}, {T}, Sacrifice this land: Search your library for up to two basic land cards that share a land type, put them onto the battlefield tapped, then shuffle.

{T}: Add {U}. Channel — {3}{U}, Discard this card: Return target artifact, creature, enchantment, or planeswalker to its owner's hand. This ability costs {1} less to activate for each legendary creature you control.

This land enters 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.)

This land enters tapped unless you have two or more opponents. {T}: Add {G} or {U}.

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

{T}: Add {C}. {4}, {T}: Target creature can't be blocked this turn.

As this land enters, 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.

This land enters tapped. When this land enters, return a land you control to its owner's hand. {T}: Add {G}{U}.

As this land enters, 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.

Islandwalk (This creature can't be blocked as long as defending player controls an Island.) When this creature enters, you may search your library for a Merfolk card, reveal it, then shuffle and put that card on top.

{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 this creature, draw a card, then discard a card.

Islandwalk (This creature can't be blocked as long as defending player controls an Island.) Whenever this creature deals combat damage to a player, you may draw that many cards.

Look at the top five cards of your library, then put them back in any order.

Draw a card for each creature you control with a +1/+1 counter on it. Those creatures gain indestructible until end of turn. (Damage and effects that say "destroy" don't destroy them.)

When this creature enters, it explores, then it explores again. (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. Then repeat this process.)

As this enchantment enters, choose a creature type. Whenever a creature you control of the chosen type enters or attacks, draw a card.

Tap another untapped Merfolk you control: Kumena can't be blocked this turn. Tap three untapped Merfolk you control: Draw a card. Tap five untapped Merfolk you control: Put a +1/+1 counter on each Merfolk you control.

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}.

Whenever a creature you control enters, 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 the creature, then put the card back or put it into your graveyard.)

Changeling (This card is every creature type.) As this creature enters, choose a creature type. You may look at the top card of your library any time. You may cast creature spells of the chosen type from the top of your library.

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

Each other Wizard creature you control enters 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.

Svyelun 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}.)

Vanishing 2 (This creature enters with two time counters on it. At the beginning of your upkeep, remove a time counter from it. When the last is removed, sacrifice it.) Whenever a player casts their second spell each turn, proliferate. (Choose any number of permanents and/or players, then give each another counter of each kind already there.)

Landfall — Whenever a land you control enters, proliferate. (Choose any number of permanents and/or players, then give each another counter of each kind already there.)

Return all attacking creatures to their owner's hand.

Destroy target permanent. Its controller creates a 3/3 green Beast creature token.

Counter target creature spell. Draw a card.

Counter target spell.

Counter target noncreature spell.

Choose two — • Return target creature or planeswalker to its owner's hand. • Counter target artifact or enchantment spell. • Put two +1/+1 counters on target creature. • Target player shuffles up to three target cards from their graveyard into their library.

Destroy target creature. It can't be regenerated. That creature's controller creates a 3/3 green Frog Lizard creature token.

Exile target artifact or creature. Its controller creates a 1/1 blue Bird creature token with flying. Foretell {U} (During your turn, you may pay {2} and exile this card from your hand face down. Cast it on a later turn for its foretell cost.)

Counter target spell. Create X Treasure tokens, where X is that spell's mana value. (They're artifacts with "{T}, Sacrifice this token: Add one mana of any color.")

Whenever this creature becomes tapped, you may pay {1}{U}. If you do, return target permanent to its owner's hand.

Kicker {X}. X can't be 0. (You may pay an additional {X} as you cast this spell.) Flying When this creature enters, if it was kicked, gain control of target artifact with mana value X or less. If that artifact is an Equipment, attach it to this creature.

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