Thwart

You may return three Islands you control to their owner's hand rather than pay this spell's mana cost.
Counter target spell.

Compulsive Research

Target player draws three cards. Then that player discards two cards unless they discard a land card.

Solemn Simulacrum

When this creature enters, you may search your library for a basic land card, put that card onto the battlefield tapped, then shuffle.
When this creature dies, you may draw a card.

Trade Routes

{1}: Return target land you control to its owner's hand.
{1}, Discard a land card: Draw a card.

Island

Floodchaser

Floodchaser enters with six +1/+1 counters on it.
Floodchaser can't attack unless defending player controls an Island.
{U}, Remove a +1/+1 counter from Floodchaser: Target land becomes an Island until end of turn.

Saprazzan Skerry

Saprazzan Skerry enters tapped with two depletion counters on it.
{T}, Remove a depletion counter from Saprazzan Skerry: Add {U}{U}. If there are no depletion counters on Saprazzan Skerry, sacrifice it.

Sea's Claim

Enchant land (Target a land as you cast this. This card enters attached to that land.)
Enchanted land is an Island.

Wu Admiral

Wu Admiral gets +1/+1 as long as an opponent controls an Island.

Mystic Compass

{1}, {T}: Target land becomes the basic land type of your choice until end of turn.

Hammerhead Shark

Hammerhead Shark can't attack unless defending player controls an Island.

Lotus Field

Hexproof
Lotus Field enters tapped.
When Lotus Field enters, sacrifice two lands.
{T}: Add three mana of any one color.

Lingering Mirage

Enchant land
Enchanted land is an Island.
Cycling {2} ({2}, Discard this card: Draw a card.)

Dreamwinder

Dreamwinder can't attack unless defending player controls an Island.
{U}, Sacrifice an Island: Target land becomes an Island until end of turn.

Patron of the Moon

Moonfolk offering (You may cast this spell any time you could cast an instant by sacrificing a Moonfolk and paying the difference in mana costs between this and the sacrificed Moonfolk. Mana cost includes color.)
Flying
{1}: Put up to two land cards from your hand onto the battlefield tapped.

Dreamscape Artist

{2}{U}, {T}, Discard a card, Sacrifice a land: Search your library for up to two basic land cards, put them onto the battlefield, then shuffle.

Thirst for Knowledge

Draw three cards. Then discard two cards unless you discard an artifact card.

Streambed Aquitects

{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.

Soratami Cloudskater

Flying
{2}, Return a land you control to its owner's hand: Draw a card, then discard a card.

Vodalian Serpent

Kicker {2} (You may pay an additional {2} as you cast this spell.)
Vodalian Serpent can't attack unless defending player controls an Island.
If Vodalian Serpent was kicked, it enters with four +1/+1 counters on it.

Tragic Lesson

Draw two cards. Then discard a card unless you return a land you control to its owner's hand.

Retraced Image

Reveal a card in your hand, then put that card onto the battlefield if it has the same name as a permanent.

Thirst for Meaning

Draw three cards. Then discard two cards unless you discard an enchantment card.

Slipstream Eel

Slipstream Eel can't attack unless defending player controls an Island.
Cycling {1}{U} ({1}{U}, Discard this card: Draw a card.)

Sol Ring

Tideshaper Mystic

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

Reef Shaman

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

Drownyard Temple

{T}: Add {C}.
{3}: Return Drownyard Temple from your graveyard to the battlefield tapped.

Sealock Monster

Sealock Monster can't attack unless defending player controls an Island.
{5}{U}{U}: Monstrosity 3. (If this creature isn't monstrous, put three +1/+1 counters on it and it becomes monstrous.)
When Sealock Monster becomes monstrous, target land becomes an Island in addition to its other types.

Dream Thrush

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

Convincing Mirage

Enchant land
As Convincing Mirage enters, choose a basic land type.
Enchanted land is the chosen type.

Moonbow Illusionist

Flying
{2}, Return a land you control to its owner's hand: Target land becomes the basic land type of your choice until end of turn.

Spreading Seas

Enchant land
When Spreading Seas enters, draw a card.
Enchanted land is an Island.

Thespian's Stage

{T}: Add {C}.
{2}, {T}: Thespian's Stage becomes a copy of target land, except it has this ability.

Tideforce Elemental

{U}, {T}: You may tap or untap another target creature.
Landfall — Whenever a land you control enters, you may untap Tideforce Elemental.

Field of Ruin

{T}: Add {C}.
{2}, {T}, Sacrifice Field of Ruin: Destroy target nonbasic land an opponent controls. Each player searches their library for a basic land card, puts it onto the battlefield, then shuffles.

Temple of the False God

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

Rogue's Passage

{T}: Add {C}.
{4}, {T}: Target creature can't be blocked this turn.

Glasspool Shore

Glasspool Shore enters tapped.
{T}: Add {U}.

Glasspool Mimic

You may have Glasspool Mimic enter as a copy of a creature you control, except it's a Shapeshifter Rogue in addition to its other types.

Glasspool Mimic // Glasspool Shore

Tidal Bore

You may return an Island you control to its owner's hand rather than pay this spell's mana cost.
You may tap or untap target creature.

Burnished Hart

{3}, Sacrifice this creature: Search your library for up to two basic land cards, put them onto the battlefield tapped, then shuffle.

Deep-Sea Serpent

Deep-Sea Serpent can't attack unless defending player controls an Island.

Zhou Yu, Chief Commander

Zhou Yu, Chief Commander can't attack unless defending player controls an Island.

Frantic Search

Draw two cards, then discard two cards. Untap up to three lands.

Staff of the Mind Magus

Whenever you cast a blue spell or an Island you control enters, you gain 1 life.

Fact or Fiction

Reveal the top five cards of your library. An opponent separates those cards into two piles. Put one pile into your hand and the other into your graveyard.

Steam Frigate

Steam Frigate can't attack unless defending player controls an Island.

Coral Atoll

Coral Atoll enters tapped.
When Coral Atoll enters, sacrifice it unless you return an untapped Island you control to its owner's hand.
{T}: Add {C}{U}.

Castle Vantress

Castle Vantress enters tapped unless you control an Island.
{T}: Add {U}.
{2}{U}{U}, {T}: Scry 2.

Tidal Warrior

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

Wu Warship

Wu Warship can't attack unless defending player controls an Island.

Armored Galleon

Armored Galleon can't attack unless defending player controls an Island.

Red Cliffs Armada

Red Cliffs Armada can't attack unless defending player controls an Island.

Walking Atlas

{T}: You may put a land card from your hand onto the battlefield.

Ensnare

You may return two Islands you control to their owner's hand rather than pay this spell's mana cost.
Tap all creatures.

Sea Monster

Sea Monster can't attack unless defending player controls an Island.

Retreat to Coralhelm

Landfall — Whenever a land you control enters, choose one —
• You may tap or untap target creature.
• Scry 1. (Look at the top card of your library. You may put that card on the bottom.)

Oboro Breezecaller

Flying
{2}, Return a land you control to its owner's hand: Untap target land.

Foil

You may discard an Island card and another card rather than pay this spell's mana cost.
Counter target spell.

Meloku the Clouded Mirror

Flying
{1}, Return a land you control to its owner's hand: Create a 1/1 blue Illusion creature token with flying.

Flooded Shoreline

{U}{U}, Return two Islands you control to their owner's hand: Return target creature to its owner's hand.

Terrain Generator

{T}: Add {C}.
{2}, {T}: You may put a basic land card from your hand onto the battlefield tapped.

Fathom Seer

Morph—Return two Islands you control to their owner's hand. (You may cast this card face down as a 2/2 creature for {3}. Turn it face up any time for its morph cost.)
When Fathom Seer is turned face up, draw two cards.

Mystic Sanctuary

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

Scavenger Grounds

{T}: Add {C}.
{2}, {T}, Sacrifice a Desert: Exile all graveyards.

Wayfarer's Bauble

{2}, {T}, Sacrifice Wayfarer's Bauble: Search your library for a basic land card, put that card onto the battlefield tapped, then shuffle.

Daze

You may return an Island you control to its owner's hand rather than pay this spell's mana cost.
Counter target spell unless its controller pays {1}.

Phantasmal Terrain

Enchant land
As Phantasmal Terrain enters, choose a basic land type.
Enchanted land is the chosen type.

Deprive

As an additional cost to cast this spell, return a land you control to its owner's hand.
Counter target spell.

Mitotic Manipulation

Look at the top seven cards of your library. You may put one of those cards onto the battlefield if it has the same name as a permanent. Put the rest on the bottom of your library in any order.

Ethereal Whiskergill

Flying
Ethereal Whiskergill can't attack unless defending player controls an Island.

Aquitect's Will

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.

Gush

You may return two Islands you control to their owner's hand rather than pay this spell's mana cost.
Draw two cards.