Mana Maze

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

Hydroblast

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

Walking Atlas

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

Vodalian Mystic

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

Master of Waves

Protection from red
Elemental creatures you control get +1/+1.
When Master of Waves enters, create a number of 1/0 blue Elemental creature tokens equal to your devotion to blue. (Each {U} in the mana costs of permanents you control counts toward your devotion to blue.)

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.

Scuttlemutt

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

Talrand, Sky Summoner

Whenever you cast an instant or sorcery spell, create a 2/2 blue Drake creature token with flying.

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}

Sway of Illusion

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

Blue Elemental Blast

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

Arcane Signet

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

Inundate

Return all nonblue creatures to their owners' hands.

Island

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.)

Blackblade Reforged

Equipped creature gets +1/+1 for each land you control.
Equip legendary creature {3}
Equip {7}

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.

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.

Sea Kings' Blessing

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

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.

Sword of Sinew and Steel

Equipped creature gets +2/+2 and has protection from black and from red.
Whenever equipped creature deals combat damage to a player, destroy up to one target planeswalker and up to one target artifact.
Equip {2}

Blind Seer

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

Wrath of Marit Lage

When Wrath of Marit Lage enters, tap all red creatures.
Red creatures don't untap during their controllers' untap steps.

Homarid Shaman

Hibernation

Return all green permanents to their owners' hands.

Well-Laid Plans

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

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.

Final Iteration

Flying
Wizards you control get +2/+1 and have flying.
Whenever you cast an instant or sorcery spell, create a 1/1 blue Human Wizard creature token.

Docent of Perfection

Flying
Whenever you cast an instant or sorcery spell, create a 1/1 blue Human Wizard creature token. Then if you control three or more Wizards, transform Docent of Perfection.

Docent of Perfection // Final Iteration

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.

Guile

Guile can't be blocked except by three or more creatures.
If a spell or ability you control would counter a spell, instead exile that spell and you may play that card without paying its mana cost.
When Guile is put into a graveyard from anywhere, shuffle it into its owner's library.

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.

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.

Bazaar of Baghdad

{T}: Draw two cards, then discard three cards.

Shifting Sky

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

Solve the Equation

Search your library for an instant or sorcery card, reveal it, put it into your hand, then shuffle.

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.)

Fylamarid

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

Chill

Shimmer

As Shimmer enters, choose a land type.
Each land of the chosen type has phasing. (It phases in or out before its controller untaps during each of their untap steps. While it's phased out, it's treated as though it doesn't exist.)

Grand Architect

Other blue creatures you control get +1/+1.
{U}: Target artifact creature becomes blue until end of turn.
Tap an untapped blue creature you control: Add {C}{C}. Spend this mana only to cast artifact spells or activate abilities of artifacts.

King Crab

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

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.

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."

Sensei's Divining Top

{1}: Look at the top three cards of your library, then put them back in any order.
{T}: Draw a card, then put Sensei's Divining Top on top of its owner's library.

High Tide

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

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.)

Sword of the Animist

Equipped creature gets +1/+1.
Whenever equipped creature attacks, you may search your library for a basic land card, put it onto the battlefield tapped, then shuffle.
Equip {2}

Hunting Drake

Flying
When Hunting Drake enters, put target red or green creature on top of its owner's library.

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}

Tidal Visionary

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

Wash Out

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

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."

Mind Stone

{T}: Add {C}.
{1}, {T}, Sacrifice Mind Stone: Draw a card.

Insight

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

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.)

Flash Flood

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

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}

Sky Diamond

Jaded Response

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

Sol Ring

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.

Aether Gust

Choose target spell or permanent that's red or green. Its owner puts it on their choice of the top or bottom of their library.

Narset's Reversal

Copy target instant or sorcery spell, then return it to its owner's hand. You may choose new targets for the copy.

Distorting Lens

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

Neurok Stealthsuit

Equipped creature has shroud. (It can't be the target of spells or abilities.)
{U}{U}: Attach Neurok Stealthsuit to target creature you control.
Equip {1} ({1}: Attach to target creature you control. Equip only as a sorcery.)

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}