Cold-Eyed Selkie

Islandwalk (This creature can’t be blocked as long as defending player controls an Island.)
Whenever Cold-Eyed Selkie deals combat damage to a player, you may draw that many cards.

Harbor Serpent

Islandwalk (This creature can’t be blocked as long as defending player controls an Island.)
Harbor Serpent can’t attack unless there are five or more Islands on the battlefield.

Stormtide Leviathan

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.

Inkwell Leviathan

Trample
Islandwalk (This creature can’t be blocked as long as defending player controls an Island.)
Shroud (This creature can’t be the target of spells or abilities.)

Harbor Serpent

Islandwalk (This creature can’t be blocked as long as defending player controls an Island.)
Harbor Serpent can’t attack unless there are five or more Islands on the battlefield.

Lurking Crocodile

Bloodthirst 1 (If an opponent was dealt damage this turn, this creature enters the battlefield with a +1/+1 counter on it.)
Islandwalk (This creature can’t be blocked as long as defending player controls an Island.)

Wrexial, the Risen Deep

Islandwalk, swampwalk (This creature can’t be blocked as long as defending player controls an Island or a Swamp.)
Whenever Wrexial, the Risen Deep deals combat damage to a player, you may cast target instant or sorcery card from that player’s graveyard without paying its mana cost. If that spell would be put into a graveyard this turn, exile it instead.

Harbor Serpent

Islandwalk (This creature can’t be blocked as long as defending player controls an Island.)
Harbor Serpent can’t attack unless there are five or more Islands on the battlefield.

Merfolk Spy

Islandwalk (This creature can’t be blocked as long as defending player controls an Island.)
Whenever Merfolk Spy deals combat damage to a player, that player reveals a card at random from their hand.

Stormtide Leviathan

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.

River Boa

Islandwalk (This creature can’t be blocked as long as defending player controls an Island.)
: Regenerate River Boa.

Halimar Wavewatch

Level up (: Put a level counter on this. Level up only as a sorcery.)
LEVEL 1-4
0/6
LEVEL 5+
6/6
Islandwalk (This creature can’t be blocked as long as defending player controls an Island.)

Thada Adel, Acquisitor

Islandwalk (This creature can’t be blocked as long as defending player controls an Island.)
Whenever Thada Adel, Acquisitor deals combat damage to a player, search that player’s library for an artifact card and exile it. Then that player shuffles their library. Until end of turn, you may play that card.

Enclave Elite

Multikicker (You may pay an additional any number of times as you cast this spell.)
Islandwalk (This creature can’t be blocked as long as defending player controls an Island.)
Enclave Elite enters the battlefield with a +1/+1 counter on it for each time it was kicked.

Wrexial, the Risen Deep

Islandwalk, swampwalk (This creature can’t be blocked as long as defending player controls an Island or a Swamp.)
Whenever Wrexial, the Risen Deep deals combat damage to a player, you may cast target instant or sorcery card from that player’s graveyard without paying its mana cost. If that spell would be put into a graveyard this turn, exile it instead.

Merfolk Seastalkers

Islandwalk (This creature can’t be blocked as long as defending player controls an Island.)
: Tap target creature without flying.

River Boa

Islandwalk (This creature can’t be blocked as long as defending player controls an Island.)
: Regenerate River Boa.

Livonya Silone

First strike; legendary landwalk (This creature can’t be blocked as long as defending player controls a legendary land.)

Inkwell Leviathan

Trample
Islandwalk (This creature can’t be blocked as long as defending player controls an Island.)
Shroud (This creature can’t be the target of spells or abilities.)

Cold-Eyed Selkie

Islandwalk (This creature can’t be blocked as long as defending player controls an Island.)
Whenever Cold-Eyed Selkie deals combat damage to a player, you may draw that many cards.

Stonybrook Banneret

Islandwalk (This creature can’t be blocked as long as defending player controls an Island.)
Merfolk spells and Wizard spells you cast cost less to cast.

Merrow Harbinger

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 your library and put that card on top of it.

Sygg, River Guide

Islandwalk (This creature can’t be blocked as long as defending player controls an Island.)
: Target Merfolk you control gains protection from the color of your choice until end of turn.

Inkfathom Divers

Islandwalk (This creature can’t be blocked as long as defending player controls an Island.)
When Inkfathom Divers enters the battlefield, look at the top four cards of your library, then put them back in any order.

Rootwater Commando

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