Scuttlemutt

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

Quicksilver Fountain

At the beginning of each player's upkeep, that player puts a flood counter on target non-Island land they control of their choice. That land is an Island for as long as it has a flood counter on it.
At the beginning of each end step, if all lands on the battlefield are Islands, remove all flood counters from them.

Terrain Generator

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

Distorting Lens

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

Sanctuary Blade

As Sanctuary Blade becomes attached to a creature, choose a color.
Equipped creature gets +2/+0 and has protection from the last chosen color.
Equip {3}

Illusionist's Bracers

Whenever an ability of equipped creature is activated, if it isn't a mana ability, copy that ability. You may choose new targets for the copy.
Equip {3}

Tidebinder Mage

When Tidebinder Mage enters, tap target red or green creature an opponent controls. That creature doesn't untap during its controller's untap step for as long as you control Tidebinder Mage.

Detection Tower

{T}: Add {C}.
{1}, {T}: Until end of turn, your opponents and creatures your opponents control with hexproof can be the targets of spells and abilities you control as though they didn't have hexproof.

Chameleon Spirit

As Chameleon Spirit 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.

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."

Urza's Mine

{T}: Add {C}. If you control an Urza's Power-Plant and an Urza's Tower, add {C}{C} instead.

War Room

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

Ray of Frost

Flash
Enchant creature
When Ray of Frost enters, if enchanted creature is red, tap it.
As long as enchanted creature is red, it loses all abilities.
Enchanted creature doesn't untap during its controller's untap step.

Hydroblast

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

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.

Otawara, Soaring City

{T}: Add {U}.
Channel — {3}{U}, Discard Otawara, Soaring City: Return target artifact, creature, enchantment, or planeswalker to its owner's hand. This ability costs {1} less to activate for each legendary creature you control.

Jaded Response

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

Douse

Commander's Plate

Equipped creature gets +3/+3 and has protection from each color that's not in your commander's color identity.
Equip commander {3}
Equip {5}

Blue Elemental Blast

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

Wash Out

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

Mithril Coat

Flash
Indestructible
When Mithril Coat enters, attach it to target legendary creature you control.
Equipped creature has indestructible.
Equip {3}

Sapphire Medallion

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

Myriad Landscape

Myriad Landscape enters 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.

Willbreaker

Whenever a creature an opponent controls becomes the target of a spell or ability you control, gain control of that creature for as long as you control Willbreaker.

Cerulean Drake

Flying
Protection from red (This creature can't be blocked, targeted, dealt damage, enchanted, or equipped by anything red.)
Sacrifice Cerulean Drake: Counter target spell that targets you.

Sea Sprite

Archmage Emeritus

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

Chill

High Tide

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

Urza's Power Plant

{T}: Add {C}. If you control an Urza's Mine and an Urza's Tower, add {C}{C} instead.

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.)

Sword of War and Peace

Equipped creature gets +2/+2 and has protection from red and from white.
Whenever equipped creature deals combat damage to a player, Sword of War and Peace deals damage to that player equal to the number of cards in their hand and you gain 1 life for each card in your hand.
Equip {2}

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.

The Mycosynth Gardens

{T}: Add {C}.
{1}, {T}: Add one mana of any color.
{X}, {T}: The Mycosynth Gardens becomes a copy of target nontoken artifact you control with mana value X.

Mana Maze

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

Robe of the Archmagi

Whenever equipped creature deals combat damage to a player, you draw that many cards.
Equip {4}
Equip Shaman, Warlock, or Wizard {1}

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.

Sway of Illusion

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

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.

Nykthos, Shrine to Nyx

{T}: Add {C}.
{2}, {T}: Choose a color. Add an amount of mana of that color equal to your devotion to that color. (Your devotion to a color is the number of mana symbols of that color in the mana costs of permanents you control.)

Sword of Truth and Justice

Equipped creature gets +2/+2 and has protection from white and from blue.
Whenever equipped creature deals combat damage to a player, put a +1/+1 counter on a creature you control, then proliferate. (Choose any number of permanents and/or players, then give each another counter of each kind already there.)
Equip {2}

Propaganda

Creatures can't attack you unless their controller pays {2} for each creature they control that's attacking you.

Academy Ruins

{T}: Add {C}.
{1}{U}, {T}: Put target artifact card from your graveyard on top of your library.

King Crab

{1}{U}, {T}: Put target green creature on top of its owner's library.

Reliquary Tower

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

Flash Flood

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

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.)

Fylamarid

Flying
Fylamarid can't be blocked by blue creatures.
{U}: Target creature becomes blue until end of turn.

Essence Leak

Enchant permanent
As long as enchanted permanent is red or green, it has "At the beginning of your upkeep, sacrifice this permanent unless you pay its mana cost."

Nyx Lotus

Nyx Lotus enters tapped.
{T}: Choose a color. Add an amount of mana of that color equal to your devotion to that color. (Your devotion to a color is the number of mana symbols of that color in the mana costs of permanents you control.)

Island

Flashfreeze

Archaeomancer

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

Insight

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

Urza's Tower

{T}: Add {C}. If you control an Urza's Mine and an Urza's Power-Plant, add {C}{C}{C} instead.

Extraplanar Lens

Imprint — When Extraplanar Lens enters, you may exile target land you control.
Whenever a land with the same name as the exiled card is tapped for mana, its controller adds one mana of any type that land produced.

Shadowspear

Equipped creature gets +1/+1 and has trample and lifelink.
{1}: Permanents your opponents control lose hexproof and indestructible until end of turn.
Equip {2}

Sword of Hearth and Home

Equipped creature gets +2/+2 and has protection from green and from white.
Whenever equipped creature deals combat damage to a player, exile up to one target creature you own, then search your library for a basic land card. Put both cards onto the battlefield under your control, then shuffle.
Equip {2}

Mind Harness

Enchant red or green creature
Cumulative upkeep {1} (At the beginning of your upkeep, put an age counter on this permanent, then sacrifice it unless you pay its upkeep cost for each age counter on it.)
You control enchanted creature.

Riptide Laboratory

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

Shifting Sky

As Shifting Sky enters, choose a color.
All nonland permanents are the chosen color.

Sword of Light and Shadow

Equipped creature gets +2/+2 and has protection from white and from black.
Whenever equipped creature deals combat damage to a player, you gain 3 life and you may return up to one target creature card from your graveyard to your hand.
Equip {2}

Swirl the Mists

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

Sword of Once and Future

Equipped creature gets +2/+2 and has protection from blue and from black.
Whenever equipped creature deals combat damage to a player, surveil 2. Then you may cast an instant or sorcery spell with mana value 2 or less from your graveyard without paying its mana cost. If that spell would be put into your graveyard, exile it instead.
Equip {2}

Homarid Shaman

Demolition Field

{T}: Add {C}.
{2}, {T}, Sacrifice this land: Destroy target nonbasic land an opponent controls. That land's controller may search their library for a basic land card, put it onto the battlefield, then shuffle. You may search your library for a basic land card, put it onto the battlefield, then shuffle.

Soporific Springs

As Soporific Springs enters, you may pay 3 life. If you don't, it enters tapped.
{T}: Add {U}.

Sink into Stupor

Return target spell or nonland permanent an opponent controls to its owner's hand.

Sink into Stupor // Soporific Springs

Coast Watcher

Castle Vantress

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

Bandit's Haul

Whenever you commit a crime, put a loot counter on Bandit's Haul. This ability triggers only once each turn. (Targeting opponents, anything they control, and/or cards in their graveyards is a crime.)
{T}: Add one mana of any color.
{2}, {T}, Remove two loot counters from Bandit's Haul: Draw a card.

Harbinger of the Seas

Counterspell

Buried Ruin

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

Vodalian Mystic

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

Omen Hawker

{T}: Add {C}{U}. Spend this mana only to activate abilities.

Well-Laid Plans

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

Blind Seer

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

Isochron Scepter

Imprint — When Isochron Scepter 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.

Llawan, Cephalid Empress

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

Tidal Visionary

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

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.

Arcanis the Omnipotent

{T}: Draw three cards.
{2}{U}{U}: Return Arcanis to its owner's hand.

Painter's Servant

As Painter's Servant enters, choose a color.
All cards that aren't on the battlefield, spells, and permanents are the chosen color in addition to their other colors.

Orvar, the All-Form

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.

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.)

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.")