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. Until end of turn, you may play that card.

Windfall

Each player discards their hand, then draws cards equal to the greatest number of cards a player discarded this way.

Soratami Mirror-Mage

Flying
{3}, Return three lands you control to their owner's hand: Return target creature to its owner's hand.

Windrider Eel

Flying
Landfall — Whenever a land you control enters, Windrider Eel gets +2/+2 until end of turn.

Inundate

Return all nonblue creatures to their owners' hands.

Tempest Djinn

Flying
Tempest Djinn gets +1/+0 for each basic Island you control.

Flow of Ideas

Caged Sun

As Caged Sun enters, choose a color.
Creatures you control of the chosen color get +1/+1.
Whenever a land's ability causes you to add one or more mana of the chosen color, add one additional mana of that color.

Thwart

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

Sunscorched Desert

When Sunscorched Desert enters, it deals 1 damage to target player or planeswalker.
{T}: Add {C}.

Soratami Seer

Flying
{4}, Return two lands you control to their owner's hand: Discard all the cards in your hand, then draw that many cards.

Radiant Fountain

When Radiant Fountain enters, you gain 2 life.
{T}: Add {C}.

Roil Elemental

Flying
Landfall — Whenever a land you control enters, you may gain control of target creature for as long as you control Roil Elemental.

Scourge of Fleets

When Scourge of Fleets enters, 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.

Ruin Crab

Landfall — Whenever a land you control enters, each opponent mills three cards. (To mill a card, a player puts the top card of their library into their graveyard.)

Adventuring Gear

Landfall — Whenever a land you control enters, equipped creature gets +2/+2 until end of turn.
Equip {1} ({1}: Attach to target creature you control. Equip only as a sorcery.)

Altar of the Brood

Whenever another permanent you control enters, each opponent mills a card.

Ovinomancer

When Ovinomancer enters, sacrifice it unless you return three basic lands you control to their owner's hand.
{T}, Return Ovinomancer to its owner's hand: Destroy target creature. It can't be regenerated. That creature's controller creates a 0/1 green Sheep creature token.

Trinket Mage

When Trinket Mage enters, you may search your library for an artifact card with mana value 1 or less, reveal that card, put it into your hand, then shuffle.

Oboro Envoy

Flying
{2}, Return a land you control to its owner's hand: Target creature gets -X/-0 until end of turn, where X is the number of cards in your hand.

Tragic Lesson

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

Soratami Rainshaper

Flying
{3}, Return a land you control to its owner's hand: Target creature you control gains shroud until end of turn. (It can't be the target of spells or abilities.)

Flooded Shoreline

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

Soratami Cloudskater

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

Counterspell

Back to Basics

Nonbasic lands don't untap during their controllers' untap steps.

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.)

Strata Scythe

Imprint — When Strata Scythe enters, search your library for a land card, exile it, then shuffle.
Equipped creature gets +1/+1 for each land on the battlefield with the same name as the exiled card.
Equip {3}

Scaretiller

Whenever Scaretiller becomes tapped, choose one —
• You may put a land card from your hand onto the battlefield tapped.
• Return target land card from your graveyard to the battlefield tapped.

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.

Laboratory Maniac

If you would draw a card while your library has no cards in it, you win the game instead.

Soratami Mindsweeper

Flying
{2}, Return a land you control to its owner's hand: Target player mills two cards.

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.

Wave-Wing Elemental

Flying
Landfall — Whenever a land you control enters, Wave-Wing Elemental gets +2/+2 until end of turn.

Turnabout

Choose artifact, creature, or land. Tap all untapped permanents of the chosen type target player controls, or untap all tapped permanents of that type that player controls.

Storm Cauldron

Each player may play an additional land during each of their turns.
Whenever a land is tapped for mana, return it to its owner's hand.

Mana Breach

Whenever a player casts a spell, that player returns a land they control to its owner's hand.

Enter the Infinite

Draw cards equal to the number of cards in your library, then put a card from your hand on top of your library. You have no maximum hand size until your next turn.

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.

Archaeomancer

When Archaeomancer enters, return target instant or sorcery card from your graveyard to your hand.

Ensnare

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

Reliquary Tower

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

Staff of the Mind Magus

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

Horn of Greed

Whenever a player plays a land, that player draws a card.

Tideforce Elemental

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

Deprive

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

Guardian of Tazeem

Flying
Landfall — Whenever a land you control enters, tap target creature an opponent controls. If that land is an Island, that creature doesn't untap during its controller's next untap step.

Finale of Revelation

Draw X cards. If X is 10 or more, instead shuffle your graveyard into your library, draw X cards, untap up to five lands, and you have no maximum hand size for the rest of the game.
Exile Finale of Revelation.

Island

Soratami Savant

Flying
{3}, Return a land you control to its owner's hand: Counter target spell unless its controller pays {3}.

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.

Hedron Crab

Landfall — Whenever a land you control enters, target player mills three cards.

Devastation Tide

Return all nonland permanents to their owners' hands.
Miracle {1}{U} (You may cast this card for its miracle cost when you draw it if it's the first card you drew this turn.)

Walking Atlas

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

Curse of Verbosity

Enchant player
Whenever enchanted player is attacked, you draw a card. Each opponent attacking that player does the same.

Overburden

Whenever a player puts a nontoken creature onto the battlefield, that player returns a land they control to its owner's hand.

High Tide

Until end of turn, whenever a player taps an Island for mana, that player adds an additional {U}.

Kefnet the Mindful

Flying, indestructible
Kefnet the Mindful can't attack or block unless you have seven or more cards in hand.
{3}{U}: Draw a card, then you may return a land you control to its owner's hand.

Amulet of Vigor

Whenever a permanent you control enters tapped, untap it.

Training Grounds

Activated abilities of creatures you control cost {2} less to activate. This effect can't reduce the mana in that cost to less than one mana.

Floodbringer

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

Psychosis Crawler

Psychosis Crawler's power and toughness are each equal to the number of cards in your hand.
Whenever you draw a card, each opponent loses 1 life.

Gush

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

Oboro Breezecaller

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

Uyo, Silent Prophet

Flying
{2}, Return two lands you control to their owner's hand: Copy target instant or sorcery spell. You may choose new targets for the copy.

Seer's Sundial

Landfall — Whenever a land you control enters, you may pay {2}. If you do, draw a card.

Engulf the Shore

Return to their owners' hands all creatures with toughness less than or equal to the number of Islands you control.