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

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.

Equipped creature has haste and shroud. (It can't be the target of spells or abilities.) Equip {0}

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.)

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

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.)

{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.

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.

Whenever a creature you control with a +1/+1 counter on it deals combat damage to a player, you may draw 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.

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.)

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

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.

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

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

Whenever this creature becomes blocked, you may draw three cards.

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}.)

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

Whenever an opponent plays a land, you may put a land card from your hand onto the battlefield.

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}.

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.

You may have Sakashima the Impostor enter as a copy of any creature on the battlefield, except its name is Sakashima the Impostor, it's legendary in addition to its other types, and it has "{2}{U}{U}: Return Sakashima the Impostor to its owner's hand at the beginning of the next end step."

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

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

This creature can't be blocked.

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

This creature can't be blocked.

Counter target noncreature spell. Its controller creates two Treasure tokens. (They're artifacts with "{T}, Sacrifice this token: Add one mana of any color.")

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

Counter target spell.

Flash Vigilance When this creature enters, tap target creature an opponent controls and put a stun counter on it. {1}{U}, {T}: Shuffle this creature and target creature with a stun counter on it into their owners' libraries.

Destroy target artifact or enchantment. Its controller gains 4 life.

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

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

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

Flash When this creature enters, counter up to one target activated or triggered ability. If an ability of an artifact, creature, or planeswalker is countered this way, that permanent loses all abilities for as long as this creature remains on the battlefield. (Mana abilities can't be targeted.)

Until end of turn, creatures you control gain trample and get +X/+X, where X is the greatest power among creatures you control.

{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.

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.

Landfall — Whenever a land you control enters, put a +1/+1 counter on target creature. {3}{G}{G}: Double the number of +1/+1 counters on each creature you control.

When this enchantment enters, you become the monarch. At the beginning of your upkeep, distribute two +1/+1 counters among up to two target creatures. Then if you're the monarch, double the number of +1/+1 counters on each creature you control.

If an effect would create one or more tokens under your control, it creates twice that many of those tokens instead. If an effect would put one or more counters on a permanent you control, it puts twice that many of those counters on that permanent instead.

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.

If one or more +1/+1 counters would be put on an artifact or creature you control, that many plus one +1/+1 counters are put on it instead. {1}{G}, {T}: Put a +1/+1 counter on target artifact or creature you control. Activate only as a sorcery. Cycling {2} ({2}, Discard this card: Draw a card.)

If one or more tokens would be created, twice that many of those tokens are created instead. If one or more +1/+1 counters would be put on a creature, twice that many +1/+1 counters are put on that creature instead.

Whenever a creature you control leaves the battlefield, if it had counters on it, put those counters on The Ozolith. At the beginning of combat on your turn, if The Ozolith has counters on it, you may move all counters from The Ozolith onto target 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 {G} or {U}.) As this land enters, you may pay 2 life. If you don't, it enters tapped.

{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}.)

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

({T}: Add {U}.)

{T}, Pay 1 life, Sacrifice this land: Search your library for a Forest or Island card, put it onto the battlefield, then shuffle.

({T}: Add {U}.) This land enters tapped unless you control three or more other Islands. When this land enters untapped, you may put target instant or sorcery card from your graveyard on top of your library.

{T}: Add one mana of any type that a land you control could produce.

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}.

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 Three Tree City enters, choose a creature type. {T}: Add {C}. {2}, {T}: Choose a color. Add an amount of mana of that color equal to the number of creatures you control of the chosen type.

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.