At the beginning of combat on your turn, this creature explores. Then you may have it become a copy of another creature you control until end of turn. (To have this creature explore, 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 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.

This creature can't be blocked. This creature gets +2/+0 as long as you control a commander that's a creature or planeswalker.

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 a creature you control explores, this creature gets +1/+0 until end of turn and can't be blocked this turn.

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

Flying When this creature enters, put a +1/+1 counter on target creature you control. {3}{G}{U}: Proliferate. (Choose any number of permanents and/or players, then give each another counter of each kind already there.)

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.

This creature can't be blocked.

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.

This creature can't be blocked. Whenever another Merfolk you control enters, this creature gets +1/+1 until end of turn.

Vigilance Whenever this creature enters or attacks, create a Map token. (It's an artifact with "{1}, {T}, Sacrifice this token: Target creature you control explores. Activate only as a sorcery.")

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.

You may have this creature enter as a copy of a creature or planeswalker you control, except it enters with an additional +1/+1 counter on it if it's a creature, it enters with an additional loyalty counter on it if it's a planeswalker, and it isn't legendary.

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.

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}.)

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.

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.

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

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

{T}: Untap another target permanent.

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.)

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.)

Indestructible As long as your devotion to blue is less than five, Thassa isn't a creature. (Each {U} in the mana costs of permanents you control counts toward your devotion to blue.) At the beginning of your upkeep, scry 1. {1}{U}: Target creature you control can't be blocked this turn.

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.

Delve (Each card you exile from your graveyard while casting this spell pays for {1}.) Look at the top seven cards of your library. Put two of them into your hand and the rest on the bottom of your library in any order.

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.

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

Choose three. You may choose the same mode more than once. • Counter target spell unless its controller pays {3}. • Return target creature to its owner's hand. • Draw a card.

Prime Speaker Zegana enters with X +1/+1 counters on it, where X is the greatest power among other creatures you control. When Prime Speaker Zegana enters, draw cards equal to its power.

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

({U/P} can be paid with either {U} or 2 life.) Draw two cards, then proliferate. (Choose any number of permanents and/or players, then give each another counter of each kind already there.)

As this creature enters, choose a creature type. This creature is the chosen type in addition to its other types. Whenever this creature enters or attacks, you may draw a card for each other creature you control that shares a creature type with it. If you do, discard a card.

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

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

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

({T}: Add {G}.)

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

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

({T}: Add {U}.)

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.)

({T}: Add {G} or {U}.) This land enters tapped.

{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}.

({T}: Add {G} or {U}.) This land enters tapped.

This land enters tapped. When this land enters, scry 1. (Look at the top card of your library. You may put that card on the bottom.) {T}: Add {G} or {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.

As this land enters, you may reveal a Forest or Island card from your hand. If you don't, this land enters tapped. {T}: Add {G} or {U}.

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

Enchant creature, land, or planeswalker Enchanted permanent is a colorless land with "{T}: Add {C}" and loses all other card types and abilities.

Changeling (This card is every creature type.) When this creature enters, you may exile a creature card from your graveyard. If you do, exile target artifact or enchantment an opponent controls.

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.

Exile target creature. Its controller manifests the top card of their library. (That player puts the top card of their library onto the battlefield face down as a 2/2 creature. If it's a creature card, it can be turned face up any time for its mana cost.)

Exile target artifact or creature. Its controller creates a 4/4 blue and red Elemental creature token.

Counter target spell.

Counter target spell with mana value 4 or greater.

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

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.

Other green creatures you control get +1/+1. Other blue creatures you control get +1/+1. Untap all green and/or blue creatures you control during each other player's untap step.

Return six target nonland permanents to their owners' hands.