{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.

Mentor (Whenever this creature attacks, put a +1/+1 counter on target attacking creature with lesser power.) Creatures you control have "Whenever one or more counters are put on this creature for the first time each turn, draw a card."

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.

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 Kiora enters, draw two cards, then discard two cards. Threshold — Whenever Kiora attacks, if there are seven or more cards in your graveyard, you may create Scion of the Deep, a legendary 8/8 blue Octopus creature token.

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.

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

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.

Choose one — • Draw cards equal to the greatest power among non-Human creatures you control. • Non-Human creatures you control get +3/+3 until end of turn.

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}.)

Landfall — Whenever a land you control enters, you gain 1 life and draw a card.

When this creature enters, create a Map token. (It's an artifact with "{1}, {T}, Sacrifice this token: Target creature you control explores. Activate only as a sorcery.") If a creature you control would explore, instead it explores, then it explores again.

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

Destroy target creature. It can't be regenerated. Its controller creates a 3/3 green Ape creature token.

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

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

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.)

Other Merfolk you control get +1/+1.

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

Other Merfolk creatures you control get +1/+1. Whenever you cast a Merfolk spell, you may tap or untap target permanent.

Flying Other Merfolk you control get +1/+0 and have flying. Encore {5}{U}{U} ({5}{U}{U}, Exile this card from your graveyard: For each opponent, create a token copy that attacks that opponent this turn if able. They gain haste. Sacrifice them at the beginning of the next end step. Activate only as a sorcery.)

Permanents you control gain hexproof and indestructible until end of turn.

(Gain the next level as a sorcery to add its ability.) At the beginning of combat on your turn, put a +1/+1 counter on target creature you control. {G}: Level 2 Permanents you control with counters on them have ward {1}. {3}{G}: Level 3 If you would put one or more counters on a permanent or player, put twice that many of each of those kinds of counters on that permanent or player instead.

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.

Permanents you control with counters on them gain hexproof and indestructible until end of turn. Prevent all damage that would be dealt to those permanents this turn. Proliferate. (Choose any number of permanents and/or players, then give each another counter of each kind already there.)

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.)

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

Choose a creature type. Return all creatures that aren't of the chosen type to their owners' hands.

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

When this enchantment enters, you become the monarch. At the beginning of your upkeep, you may put a land card from your hand onto the battlefield. If you're the monarch, instead you may put a creature or land card from your hand onto the battlefield.

Search your library for a Plains, Island, Swamp, or Mountain card, put it onto the battlefield tapped, then shuffle.

{T}: Add {C}. {1}, {T}, Sacrifice this artifact: Draw a card.

Search your library for a Forest card, put that card onto the battlefield, 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.

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

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

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}: Add {C}. {T}: Add {G} or {U}. This artifact deals 1 damage to you.

When this creature enters, you may search your library for a Merfolk card, reveal it, then shuffle and put that card on top. Whenever another Merfolk you control enters, put a +1/+1 counter on this creature.

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.

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

{T}: Add {U}. This land deals 1 damage to you. Threshold — {U}, {T}, Sacrifice this land: Target player draws three cards, then discards three cards. Activate only if seven or more cards are in your graveyard.

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

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

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

({T}: Add {G}.)

({T}: Add {G}.)

({T}: Add {G} or {U}.) This land enters tapped. When this land enters, surveil 1. (Look at the top card of your library. You may put it into your graveyard.)

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

{T}, Pay 1 life: Add one mana of any type that a land you control could produce. {3}, {T}: You may put a land card from your hand onto the battlefield tapped. {1}, {T}, Sacrifice this land: Draw a card.

({T}: Add {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.)

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 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}.

Rivendell enters tapped unless you control a legendary creature. {T}: Add {U}. {1}{U}, {T}: Scry 2. Activate only if you control a legendary creature.

{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 unless you control a Forest. {T}: Add {G}. Delirium — {2}{G}{G}: This land becomes a copy of target permanent card in your graveyard until end of turn. Activate only if there are four or more card types among cards in your graveyard.

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

{T}: Add {C}. {4}: This land becomes a 3/3 creature with vigilance and all creature types. It's still a land.

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.

{T}, Pay 1 life: Add {G} or {U}. {1}, {T}, Sacrifice this land: Draw a card.

{T}: Add {C}. {T}: Add {G} or {U}. This land deals 1 damage to you.