Flash Flood

Choose one —
• Destroy target red permanent.
• Return target Mountain to its owner's hand.

Heartstone

Activated abilities of creatures cost {1} less to activate. This effect can't reduce the mana in that cost to less than one mana.

Archway of Innovation

This land enters tapped unless you control an Island.
{T}: Add {U}.
{U}, {T}: The next spell you cast this turn has improvise. (Your artifacts can help cast that spell. Each artifact you tap after you're done activating mana abilities pays for {1}.)

Exotic Orchard

{T}: Add one mana of any color that a land an opponent controls could produce.

Chameleon Spirit

As this creature enters, choose a color.
Chameleon Spirit's power and toughness are each equal to the number of permanents of the chosen color your opponents control.

Darksteel Citadel

Riptide Laboratory

{T}: Add {C}.
{1}{U}, {T}: Return target Wizard you control to its owner's hand.

Cephalid Coliseum

{T}: Add {U}. This land deals 1 damage to you.
Threshold — {U}, {T}, Sacrifice this land: Target player draws three cards, then discards three cards. Activate only if there are seven or more cards in your graveyard.

Command Tower

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

Neutralizing Blast

Vodalian Mystic

{T}: Target instant or sorcery spell becomes the color of your choice.

Mind Stone

{T}: Add {C}.
{1}, {T}, Sacrifice this artifact: Draw a card.

Isochron Scepter

Imprint — When this artifact enters, you may exile an instant card with mana value 2 or less from your hand.
{2}, {T}: You may copy the exiled card. If you do, you may cast the copy without paying its mana cost.

Mind Bend

Change the text of target permanent by replacing all instances of one color word with another or one basic land type with another. (For example, you may change "nonblack creature" to "nongreen creature" or "forestwalk" to "islandwalk." This effect lasts indefinitely.)

Insight

Whenever an opponent casts a green spell, you draw a card.

War Room

{T}: Add {C}.
{3}, {T}, Pay life equal to the number of colors in your commanders' color identity: Draw a card.

Harbinger of the Seas

Island

Reliquary Tower

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

Myriad Landscape

This land enters tapped.
{T}: Add {C}.
{2}, {T}, Sacrifice this land: Search your library for up to two basic land cards that share a land type, put them onto the battlefield tapped, then shuffle.

Halimar Depths

This land enters tapped.
When this land enters, look at the top three cards of your library, then put them back in any order.
{T}: Add {U}.

Archmage Emeritus

Magecraft — Whenever you cast or copy an instant or sorcery spell, draw a card.

Mistrise Village

This land enters tapped unless you control a Mountain or a Forest.
{T}: Add {U}.
{U}, {T}: The next spell you cast this turn can't be countered.

Balduvian Shaman

{T}: Change the text of target white enchantment you control that doesn't have cumulative upkeep by replacing all instances of one color word with another. (For example, you may change "black creatures can't attack" to "blue creatures can't attack.") That enchantment gains "Cumulative upkeep {1}." (At the beginning of its controller's upkeep, that player puts an age counter on it, then sacrifices it unless they pay its upkeep cost for each age counter on it.)

Rogue's Passage

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

Sapphire Medallion

Blue spells you cast cost {1} less to cast.

Desert of the Mindful

This land enters tapped.
{T}: Add {U}.
Cycling {1}{U} ({1}{U}, Discard this card: Draw a card.)

Hydroblast

Choose one —
• Counter target spell if it's red.
• Destroy target permanent if it's red.

Sway of Illusion

Any number of target creatures become the color of your choice until end of turn.
Draw a card.

Scuttlemutt

{T}: Add one mana of any color.
{T}: Target creature becomes the color or colors of your choice until end of turn.

Fabricate

Search your library for an artifact card, reveal it, put it into your hand, then shuffle.

Hibernation

Return all green permanents to their owners' hands.

Sea Gate

This land enters tapped.
As this land enters, choose a color other than blue.
{T}: Add {U} or one mana of the chosen color.

Tidal Visionary

{T}: Target creature becomes the color of your choice until end of turn.

Sleight of Mind

Change the text of target spell or permanent by replacing all instances of one color word with another. (For example, you may change "target black spell" to "target blue spell." This effect lasts indefinitely.)

Riptide

Arcane Signet

Lonely Sandbar

This land enters tapped.
{T}: Add {U}.
Cycling {U} ({U}, Discard this card: Draw a card.)

Seat of the Synod

Vivid Creek

This land enters tapped with two charge counters on it.
{T}: Add {U}.
{T}, Remove a charge counter from this land: Add one mana of any color.

Rivendell

Rivendell enters tapped unless you control a legendary creature.
{T}: Add {U}.
{1}{U}, {T}: Scry 2. Activate only if you control a legendary creature.

Agna Qel'a

This land enters tapped unless you control a basic land.
{T}: Add {U}.
{2}{U}, {T}: Draw a card, then discard a card.

Swiftfoot Boots

Equipped creature has hexproof and haste. (It can't be the target of spells or abilities your opponents control. It can attack and {T} no matter when it came under your control.)
Equip {1} ({1}: Attach to target creature you control. Equip only as a sorcery.)

Thriving Isle

This land enters tapped. As it enters, choose a color other than blue.
{T}: Add {U} or one mana of the chosen color.

Archaeomancer

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

Fellwar Stone

Sunken Palace

This land enters tapped.
{T}: Add {U}.
{1}{U}, {T}, Exile seven cards from your graveyard: Add {U}. When you spend this mana to cast a spell or activate an ability, copy that spell or ability. You may choose new targets for the copy. (Mana abilities can't be copied.)

Thought Vessel

Dismiss into Dream

Each creature your opponents control is an Illusion in addition to its other types and has "When this creature becomes the target of a spell or ability, sacrifice it."

Sol Ring

Llawan, Cephalid Empress

When Llawan enters, return all blue creatures your opponents control to their owners' hands.
Your opponents can't cast blue creature spells.

Remote Isle

This land enters tapped.
{T}: Add {U}.
Cycling {2} ({2}, Discard this card: Draw a card.)

Seafloor Debris

This land enters tapped.
{T}: Add {U}.
{T}, Sacrifice this land: Add one mana of any color.

Crystal Spray

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

Deep Freeze

Enchant creature
Enchanted creature has base power and toughness 0/4, has defender, loses all other abilities, and is a blue Wall in addition to its other colors and types.

Rainbow Crow

Flying
{1}: This creature becomes the color of your choice until end of turn.

Alter Reality

Change the text of target spell or permanent by replacing all instances of one color word with another. (This effect lasts indefinitely.)
Flashback {1}{U} (You may cast this card from your graveyard for its flashback cost. Then exile it.)

Castle Vantress

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

Quickchange

Target creature becomes the color or colors of your choice until end of turn.
Draw a card.

Indigo Faerie

Flying
{U}: Target permanent becomes blue in addition to its other colors until end of turn.

Shifting Sky

As this enchantment enters, choose a color.
All nonland permanents are the chosen color.

Commander's Sphere

{T}: Add one mana of any color in your commander's color identity.
Sacrifice this artifact: Draw a card.

Douse

Wash Out

Return all permanents of the color of your choice to their owners' hands.

Mana Maze

Players can't cast spells that share a color with the spell most recently cast this turn.

Arcane Lighthouse

{T}: Add {C}.
{1}, {T}: Until end of turn, creatures your opponents control lose hexproof and shroud and can't have hexproof or shroud.

Distorting Lens

{T}: Target permanent becomes the color of your choice until end of turn.

Blue Elemental Blast

Choose one —
• Counter target red spell.
• Destroy target red permanent.

Prismwake Merrow

Flash
When this creature enters, target permanent becomes the color or colors of your choice until end of turn.

Shyft

At the beginning of your upkeep, you may have this creature become the color or colors of your choice. (This effect lasts indefinitely.)

Caged Sun

As this artifact 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 an additional one mana of that color.

Prismatic Lace

Target permanent becomes the color or colors of your choice. (This effect lasts indefinitely.)

Glamerdye

Change the text of target spell or permanent by replacing all instances of one color word with another.
Retrace (You may cast this card from your graveyard by discarding a land card in addition to paying its other costs.)

Trait Doctoring

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.)

Cowardice

Whenever a creature becomes the target of a spell or ability, return that creature to its owner's hand. (It won't be affected by the spell or ability.)

Swirl the Mists

As this enchantment enters, choose a color word.
All instances of color words in the text of spells and permanents are changed to the chosen color word.

Spectral Shift

Choose one —
• Change the text of target spell or permanent by replacing all instances of one basic land type with another. (This effect lasts indefinitely.)
• Change the text of target spell or permanent by replacing all instances of one color word with another. (This effect lasts indefinitely.)
Entwine {2} (Choose both if you pay the entwine cost.)

Buried Ruin

{T}: Add {C}.
{2}, {T}, Sacrifice this land: Return target artifact card from your graveyard to your hand.

Barrin's Unmaking

Return target permanent to its owner's hand if that permanent shares a color with the most common color among all permanents or a color tied for most common.

Sky Diamond

This artifact enters tapped.
{T}: Add {U}.

High Tide

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

Jaded Response

Counter target spell if it shares a color with a creature you control.

Well-Laid Plans

Prevent all damage that would be dealt to a creature by another creature if they share a color.

Holdout Settlement

{T}: Add {C}. ({C} represents colorless mana.)
{T}, Tap an untapped creature you control: Add one mana of any color.

Blind Seer

{1}{U}: Target spell or permanent becomes the color of your choice until end of turn.

Sisay's Ingenuity

Enchant creature
When this Aura enters, draw a card.
Enchanted creature has "{2}{U}: Target creature becomes the color of your choice until end of turn."

Negate

Ponder

Look at the top three cards of your library, then put them back in any order. You may shuffle.
Draw a card.

Mystic Sanctuary

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

Brilliant Spectrum

Converge — Draw X cards, where X is the number of colors of mana spent to cast this spell. Then discard two cards.

Sea Kings' Blessing

One or more target creatures become blue until end of turn.

Dream Coat

Enchant creature
{0}: Enchanted creature becomes the color or colors of your choice. Activate only once each turn.

Govern the Guildless

Gain control of target monocolored creature.
Forecast — {1}{U}, Reveal this card from your hand: Target creature becomes the color or colors of your choice until end of turn. (Activate only during your upkeep and only once each turn.)

Whim of Volrath

Buyback {2} (You may pay an additional {2} as you cast this spell. If you do, put this card into your hand as it resolves.)
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. (For example, you may change "nonred creature" to "nongreen creature" or "plainswalk" to "swampwalk.")

Hall of Tagsin

{T}: Add {C}.
{1}, {T}: Add one mana of any color.
{4}, {T}: Create a tapped Powerstone token. (It's an artifact with "{T}: Add {C}. This mana can't be spent to cast a nonartifact spell.")