Thought Vessel

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

Shifting Sky

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

Grafdigger's Cage

Creature cards in graveyards and libraries can't enter the battlefield.
Players can't cast spells from graveyards or libraries.

Thran Dynamo

Counterspell

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.)

High Tide

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

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.

War Room

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

Burnished Hart

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

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.

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.

Reliquary Tower

Tidal Visionary

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

Douse

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.

Consign to Dream

Return target permanent to its owner's hand. If that permanent is red or green, put it on top of its owner's library instead.

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}

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.

Azami, Lady of Scrolls

Tap an untapped Wizard you control: Draw a card.

Jaded Response

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

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."

Insight

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

Arcane Signet

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

Hydroblast

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

Vodalian Mystic

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

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.

King Crab

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

Riptide Laboratory

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

Flashfreeze

Hibernation

Return all green permanents to their owners' hands.

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.

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."

Flash Flood

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

Blue Elemental Blast

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

Sky Diamond

Distorting Lens

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

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.

Scuttlemutt

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

Seat of the Synod

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.