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

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

Flying When Merfolk Skydiver enters the battlefield, 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.)

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

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.)

Mentor (Whenever this creature attacks, put a +1/+1 counter on target attacking creature with lesser power.) Whenever a creature you control with a +1/+1 counter on it dies, draw a card.

Return target creature to its owner's hand. If it was tapped, create a Map token. (It's an artifact with "{1}, {T}, Sacrifice this artifact: Target creature you control explores. Activate only as a sorcery.")

When Cenote Scout enters the battlefield, 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 this creature, then put the card back or put it into your graveyard.)

At the beginning of combat on your turn, Deepfathom Echo 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.)

Equipped creature has "You may look at the top card of your library any time" and "Whenever this creature attacks, 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 that creature, then put the card back or put it into your graveyard.) Equip {2}

When Jadelight Ranger enters the battlefield, 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.)

When Jadelight Spelunker enters the battlefield, it explores X times. (To have it 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 that creature, then put the card back or put it into your graveyard.)

When Merfolk Branchwalker enters the battlefield, 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 this creature, then put the card back or put it into your graveyard.)

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

Whenever a creature enters the battlefield under your control, 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.)

Vigilance When River Herald Guide enters the battlefield, 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 this creature, then put the card back or put it into your graveyard.)

When River Herald Scout enters the battlefield, 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 this creature, then put the card back or put it into your graveyard.)

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

When Tishana's Wayfinder enters the battlefield, 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 this creature, then put the card back or put it into your graveyard.)

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

Flying When Waterwind Scout enters the battlefield, create a Map token. (It's an artifact with "{1}, {T}, Sacrifice this artifact: Target creature you control explores. Activate only as a sorcery.")

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

Flash When Merfolk Trickster enters the battlefield, tap target creature an opponent controls. It loses all abilities until end of turn.

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

When Tidebinder Mage enters the battlefield, tap target red or green creature an opponent controls. That creature doesn't untap during its controller's untap step for as long as you control Tidebinder Mage.

{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.

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

({T}: Add {G}.)

({T}: Add {U}.)

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

{T}: Add {C}. {G}{U}, {T}: Put a +1/+1 counter on each creature that entered the battlefield this turn.

Oran-Rief, the Vastwood enters the battlefield tapped. {T}: Add {G}. {T}: Put a +1/+1 counter on each green creature that entered the battlefield this turn.

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.)

Quandrix Campus enters the battlefield tapped. {T}: Add {G} or {U}. {4}, {T}: Scry 1.

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

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.

Simic Growth Chamber enters the battlefield tapped. When Simic Growth Chamber enters the battlefield, return a land you control to its owner's hand. {T}: Add {G}{U}.

Temple of Mystery enters the battlefield tapped. When Temple of Mystery enters the battlefield, scry 1. {T}: Add {G} or {U}.

{T}: Add {C}{C}. Activate only if you control five or more lands.

{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.

Woodland Stream enters the battlefield tapped. {T}: Add {G} or {U}.

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.

At the beginning of combat on your turn, each Merfolk creature you control 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 exploring creature, then put the card back or put it into your graveyard.) Whenever Hakbal of the Surging Soul attacks, you may put a land card from your hand onto the battlefield. If you don't, 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.

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, Current Conductor.

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

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}.)

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

Land creatures you control have flying. Whenever a land enters the battlefield under your control, if you control seven or more lands, up to one target land you control becomes a 3/3 Elemental creature with haste. It's still a land.

Tishana, Voice of Thunder's power and toughness are each equal to the number of cards in your hand. You have no maximum hand size. When Tishana enters the battlefield, draw a card for each creature you control.

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

Level up {1} ({1}: Put a level counter on this. Level up only as a sorcery.) LEVEL 2-3 3/3 Flying LEVEL 4+ 4/4 Flying Other Merfolk creatures you control get +1/+1.

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

Merfolk and Druid cards in your graveyard have retrace. (You may cast cards with retrace from your graveyard by discarding a land card in addition to paying their other costs.)

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.)

When Forerunner of the Heralds enters the battlefield, you may search your library for a Merfolk card, reveal it, then shuffle and put that card on top. Whenever another Merfolk enters the battlefield under your control, put a +1/+1 counter on Forerunner of the Heralds.

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.

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.

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

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.)

River Sneak can't be blocked. Whenever another Merfolk enters the battlefield under your control, River Sneak gets +1/+1 until end of turn.

Whenever Sage of the Falls or another non-Human creature enters the battlefield under your control, you may draw a card. If you do, discard a card.

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

Flash When Singer of Swift Rivers enters the battlefield, 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.

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.

Flash When Swift Warden enters the battlefield, target Merfolk you control gains hexproof until end of turn. (It can't be the target of spells or abilities your opponents control.)

Blue creatures you control can't be blocked.

When Tempest Caller enters the battlefield, tap all creatures target opponent controls.