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.

Tidal Control

Cumulative upkeep {2} (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.)
Pay 2 life or {2}: Counter target red or green spell. Any player may activate this ability.

Llawan, Cephalid Empress

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

Chill

Well-Laid Plans

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

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.

Mystical Tutor

Search your library for an instant or sorcery card, reveal it, then shuffle and put that card on top.

Flash Flood

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

Ether Well

Put target creature on top of its owner's library. If that creature is red, you may put it on the bottom of its owner's library instead.

Swirl the Mists

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

Vodalian Mystic

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

Shifting Sky

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

Capsize

Buyback {3} (You may pay an additional {3} as you cast this spell. If you do, put this card into your hand as it resolves.)
Return target permanent to its owner's hand.

Dust Bowl

{T}: Add {C}.
{3}, {T}, Sacrifice a land: Destroy target nonbasic land.

Brainstorm

Draw three cards, then put two cards from your hand on top of your library in any order.

Chameleon Spirit

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

King Crab

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

Caged Sun

As Caged Sun enters the battlefield, 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.

Counterspell

Snow-Covered Island

Tidal Visionary

{T}: Target 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.)

Blind Seer

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

Sea Kings' Blessing

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

Hibernation

Return all green permanents to their owners' hands.

Scrying Sheets

{T}: Add {C}.
{1}{S}, {T}: Look at the top card of your library. If that card is snow, you may reveal it and put it into your hand. ({S} can be paid with one mana from a snow source.)

Back to Basics

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

Sway of Illusion

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

Long-Term Plans

Search your library for a card, then shuffle and put that card third from the top.

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.

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.)

Wash Out

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

Insight

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

Master of Waves

Protection from red
Elemental creatures you control get +1/+1.
When Master of Waves enters the battlefield, 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.)

Sol Ring

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.

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."

Mystic Confluence

Choose three. You may choose the same mode more than once.
• Counter target spell unless its controller pays {3}.
• Return target creature to its owner's hand.
• Draw a card.

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.")

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.

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.

Jaded Response

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

Govern the Guildless

Gain control of target monocolored creature.
Forecast — {1}{U}, Reveal Govern the Guildless 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.)

Hydroblast

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

Myriad Landscape

Myriad Landscape enters the battlefield 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.

Dream Tides

Creatures don't untap during their controllers' untap steps.
At the beginning of each player's upkeep, that player may choose any number of tapped nongreen creatures they control and pay {2} for each creature chosen this way. If the player does, untap those creatures.

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.

Inundate

Return all nonblue creatures to their owners' hands.

High Tide

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

Blue Sun's Zenith

Target player draws X cards. Shuffle Blue Sun's Zenith into its owner's library.

Arcanis the Omnipotent

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

Arcane Denial

Counter target spell. Its controller may draw up to two cards at the beginning of the next turn's upkeep.
You draw a card at the beginning of the next turn's upkeep.

Empress Galina

{U}{U}, {T}: Gain control of target legendary permanent. (This effect lasts indefinitely.)

Isochron Scepter

Imprint — When Isochron Scepter enters the battlefield, 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.

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.)

Fact or Fiction

Reveal the top five cards of your library. An opponent separates those cards into two piles. Put one pile into your hand and the other into your graveyard.

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.

Douse

Tidebinder Mage

When Tidebinder Mage enters the battlefield, 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.

Wrath of Marit Lage

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

Riptide Laboratory

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

Hunting Drake

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

Mana Maze

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

Homarid Shaman

Scuttlemutt

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

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.)

Distorting Lens

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

Extraplanar Lens

Imprint — When Extraplanar Lens enters the battlefield, 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.

Reliquary Tower

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

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.)