Put a flood counter on target land. That land is an Island in addition to its other types for as long as it has a flood counter on it. If you control a Merfolk, draw a card.

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

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.

As Brass Herald enters the battlefield, choose a creature type.

When Brass Herald enters the battlefield, reveal the top four cards of your library. Put all creature cards of the chosen type revealed this way into your hand and the rest on the bottom of your library in any order.

Creatures of the chosen type get +1/+1.

Enchant creature

At the beginning of your upkeep, you may look at the top five cards of your library. If you do, you may put a creature card that shares a creature type with enchanted creature from among them onto the battlefield, then you put the rest of those cards on the bottom of your library in any order.

Target creature becomes blue until end of turn. Untap that creature.

Draw a card.

Target creature gets -4/-0 until end of turn. If you control a Wizard, draw a card.

Target creature gains flying until end of turn.

Draw a card.

Counter target spell.

Blue creatures you control can't be blocked.

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.)

Choose a creature type. Draw a card for each permanent you control of that type.

Choose one --

• Tap target permanent.

• Untap target permanent.

Entwine {1} (Choose both if you pay the entwine cost.)

Target creature gets -1/-0 until end of turn.

Draw a card.

As Heraldic Banner enters the battlefield, choose a color.

Creatures you control of the chosen color get +1/+0.

{T}: Add one mana of the chosen color.

You may tap or untap target permanent, then you may tap or untap another target permanent.

Cipher (Then you may exile this spell card encoded on a creature you control. Whenever that creature deals combat damage to a player, its controller may cast a copy of the encoded card without paying its mana cost.)

As Icon of Ancestry enters the battlefield, choose a creature type.

Creatures you control of the chosen type get +1/+1.

{3}, {T}: Look at the top three cards of your library. You may reveal a creature card of the chosen type from among them and put it into your hand. Put the rest on the bottom of your library in a random order.

({T}: Add {U}.)

({T}: Add {U}.)

({T}: Add {U}.)

({T}: Add {U}.)

({T}: Add {U}.)

({T}: Add {U}.)

({T}: Add {U}.)

({T}: Add {U}.)

({T}: Add {U}.)

({T}: Add {U}.)

({T}: Add {U}.)

({T}: Add {U}.)

({T}: Add {U}.)

({T}: Add {U}.)

({T}: Add {U}.)

({T}: Add {U}.)

({T}: Add {U}.)

({T}: Add {U}.)

({T}: Add {U}.)

({T}: Add {U}.)

({T}: Add {U}.)

({T}: Add {U}.)

({T}: Add {U}.)

({T}: Add {U}.)

({T}: Add {U}.)

({T}: Add {U}.)

({T}: Add {U}.)

({T}: Add {U}.)

({T}: Add {U}.)

Target land becomes the basic land type of your choice until end of turn.

Draw a card at the beginning of the next turn's upkeep.

Target creature gains flying until end of turn.

Draw a card.

Lonely Sandbar enters the battlefield tapped.

{T}: Add {U}.

Cycling {U} ({U}, Discard this card: Draw a card.)

Other Merfolk get +1/+1 and have islandwalk. (They can't be blocked as long as defending player controls an Island.)

Illusion creatures you control get +1/+1 and have hexproof. (They can't be the targets of spells or abilities your opponents control.)

Whenever a spell or ability you control counters a spell, you may create a 1/1 blue Merfolk creature token.

Tap seven untapped Merfolk you control: Counter target spell.

Protection from red

Elemental creatures you control get +1/+1.

When Master of Waves enters the battlefield, create a number of 1/0 blue Elemental creature tokens equal to your devotion to blue. (Each {U} in the mana costs of permanents you control counts toward your devotion to blue.)

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.

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

Islandwalk (This creature can't be blocked as long as defending player controls an Island.)

When Merrow Harbinger enters the battlefield, you may search your library for a Merfolk card, reveal it, then shuffle and put that card on top.

Other Merfolk creatures you control get +1/+1.

Whenever you cast a Merfolk spell, you may tap or untap target permanent.

{T}: Add {C}.

{1}, {T}, Sacrifice Mind Stone: Draw a card.

Flying

When Mulldrifter enters the battlefield, draw two cards.

Evoke {2}{U} (You may cast this spell for its evoke cost. If you do, it's sacrificed when it enters the battlefield.)

Myriad Landscape enters the battlefield tapped.

{T}: Add {C}.

{2}, {T}, Sacrifice Myriad Landscape: 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}.)

Mystic Sanctuary enters the battlefield tapped unless you control three or more other Islands.

When Mystic Sanctuary enters the battlefield untapped, you may put target instant or sorcery card from your graveyard on top of your library.

Convoke (Your creatures can help cast this spell. Each creature you tap while casting this spell pays for {1} or one mana of that creature's color.)

As Obelisk of Urd enters the battlefield, choose a creature type.

Creatures you control of the chosen type get +2/+2.

Changeling

Whenever you cast an instant or sorcery spell, if it targets one or more other permanents you control, create a token that's a copy of one of those permanents.

When a spell or ability an opponent controls causes you to discard this card, create a token that's a copy of target permanent.

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.)

{T}: Add {C}.

{1}, {T}: Add one mana of any color.

When Radiant Fountain enters the battlefield, you gain 2 life.

{T}: Add {C}.

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

Cycling {2} ({2}, Discard this card: Draw a card.)

As Reflections of Littjara enters the battlefield, choose a creature type.

Whenever you cast a spell of the chosen type, copy that spell. (A copy of a permanent spell becomes a token.)

When Scourge of Fleets enters the battlefield, return each creature your opponents control with toughness X or less to its owner's hand, where X is the number of Islands you control.

{T}: Add {C}.

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

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

{3}, {T}: Search your library for a Merfolk permanent card, put it onto the battlefield, then shuffle.

When you control no Islands, sacrifice Seasinger.

You may choose not to untap Seasinger during your untap step.

{T}: Gain control of target creature whose controller controls an Island for as long as you control Seasinger and Seasinger remains tapped.

Target creature gains shadow until end of turn. (It can block or be blocked by only creatures with shadow.)

Draw a card.

Target land becomes the basic land type of your choice until end of turn.

Draw a card.

Prowess (Whenever you cast a noncreature spell, this creature gets +1/+1 until end of turn.)

When Shipwreck Dowser enters the battlefield, return target instant or sorcery card from your graveyard to your hand.

As an additional cost to cast this spell, reveal a Merfolk card from your hand or pay {3}.

When Silvergill Adept enters the battlefield, draw a card.

Exile target creature you control, then return that card to the battlefield under its owner's control. If a Pirate was exiled this way, draw a card.

Sky Diamond enters the battlefield tapped.

{T}: Add {U}.

Devoid (This card has no color.)

Target creature can't be blocked this turn.

Draw a card.

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

You may have Spark Double enter the battlefield 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.

Islandwalk (This creature can't be blocked as long as defending player controls an Island.)

All lands are Islands in addition to their other types.

Creatures without flying or islandwalk can't attack.

Target creature gets -4/-0 until end of turn. If you control a Wizard, draw a card.

{T}: Target Merfolk creature gets +1/+1 and gains islandwalk until end of turn. (It can't be blocked as long as defending player controls an Island.)

{T}: Target land becomes an Island until end of turn.

If you would draw a card except the first one you draw in each of your draw steps, draw two cards instead.

Exile target permanent you control. Return that card to the battlefield under its owner's control at the beginning of the next end step. If it enters the battlefield as a creature, it enters with an additional +1/+1 counter on it.

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

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

Choose one --

• Target nonsnow permanent becomes snow until end of turn.

• Target snow permanent isn't snow until end of turn.

Draw a card at the beginning of the next turn's upkeep.

{T}: Target land becomes an Island until end of turn.

{T}: Target land becomes the basic land type of your choice until end of turn. Activate only during your turn.

Change the text of target permanent by replacing all instances of one color word with another or one basic land type with another until end of turn.

Cipher (Then you may exile this spell card encoded on a creature you control. Whenever that creature deals combat damage to a player, its controller may cast a copy of the encoded card without paying its mana cost.)

You may tap or untap target artifact, creature, or land.

Switch target creature's power and toughness until end of turn.

Draw a card.

When Watertrap Weaver enters the battlefield, tap target creature an opponent controls. That creature doesn't untap during its controller's next untap step.

Whenever you cast your first spell during each opponent's turn, draw a card.

When Whirlpool Rider enters the battlefield, shuffle the cards from your hand into your library, then draw that many cards.