Urborg, Tomb of Yawgmoth

Each land is a Swamp in addition to its other land types.

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.

Chill

Azorius Signet

Dissipation Field

Whenever a permanent deals damage to you, return it to its owner's hand.

Deathmark

Sol Ring

Smothering Tithe

Whenever an opponent draws a card, that player may pay {2}. If the player doesn't, you create a Treasure token. (It's an artifact with "{T}, Sacrifice this artifact: Add one mana of any color.")

Flood of Tears

Return all nonland permanents to their owners' hands. If you return four or more nontoken permanents you control this way, you may put a permanent card from your hand onto the battlefield.

Warped Devotion

Whenever a permanent is returned to a player's hand, that player discards a card.

Blue Elemental Blast

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

Prismatic Lace

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

Rogue's Passage

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

Tidal Visionary

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

Northern Paladin

{W}{W}, {T}: Destroy target black permanent.

Sphinx's Tutelage

Whenever you draw a card, target opponent mills two cards. If two nonland cards that share a color were milled this way, repeat this process.
{5}{U}: Draw a card, then discard a card.

Explore the Vastlands

Each player looks at the top five cards of their library and may reveal a land card and/or an instant or sorcery card from among them. Each player puts the cards they revealed this way into their hand and the rest on the bottom of their library in a random order. Each player gains 3 life.

Wandering Archaic

Whenever an opponent casts an instant or sorcery spell, they may pay {2}. If they don't, you may copy that spell. You may choose new targets for the copy.

Wandering Archaic // Explore the Vastlands

Orzhov Signet

Baleful Strix

Flying, deathtouch
When Baleful Strix enters, draw a card.

Shifting Sky

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

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.

Gonti, Lord of Luxury

Deathtouch
When Gonti, Lord of Luxury enters, look at the top four cards of target opponent's library, exile one of them face down, then put the rest on the bottom of that library in a random order. You may cast that card for as long as it remains exiled, and mana of any type can be spent to cast that spell.

Plains

Exotic Orchard

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

Dromar, the Banisher

Flying
Whenever Dromar, the Banisher deals combat damage to a player, you may pay {2}{U}. If you do, choose a color, then return all creatures of that color to their owners' hands.

Dire Undercurrents

Whenever a blue creature you control enters, you may have target player draw a card.
Whenever a black creature you control enters, you may have target player discard a card.

Flooded Woodlands

Green creatures can't attack unless their controller sacrifices a land of their choice for each green creature they control that's attacking. (This cost is paid as attackers are declared.)

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.)

Rhystic Study

Whenever an opponent casts a spell, you may draw a card unless that player pays {1}.

Mother of Runes

{T}: Target creature you control gains protection from the color of your choice until end of turn.

Eight-and-a-Half-Tails

{1}{W}: Target permanent you control gains protection from white until end of turn.
{1}: Target spell or permanent becomes white until end of turn.

Blind Seer

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

Mana Maze

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

Flash Flood

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

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.

Sway of Illusion

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

Esper Sentinel

Whenever an opponent casts their first noncreature spell each turn, draw a card unless that player pays {X}, where X is Esper Sentinel's power.

Talisman of Hierarchy

{T}: Add {C}.
{T}: Add {W} or {B}. Talisman of Hierarchy deals 1 damage to you.

Gilded Lotus

Swamp

Well-Laid Plans

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

Story Circle

As Story Circle enters, choose a color.
{W}: The next time a source of your choice of the chosen color would deal damage to you this turn, prevent that damage.

Cyclonic Rift

Return target nonland permanent you don't control to its owner's hand.
Overload {6}{U} (You may cast this spell for its overload cost. If you do, change "target" in its text to "each.")

Island

Distorting Lens

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

Hibernation

Return all green permanents to their owners' hands.

Darkest Hour

Fellwar Stone

Stormscape Familiar

Flying
White spells and black spells you cast cost {1} less to cast.

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.

Command Tower

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

Celestial Dawn

Lands you control are Plains.
Nonland permanents you control are white. The same is true for spells you control and nonland cards you own that aren't on the battlefield.
You may spend white mana as though it were mana of any color. You may spend other mana only as though it were colorless mana.

Thoughtlace

Target spell or permanent becomes blue. (Mana symbols on that permanent remain unchanged.)

Wash Out

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

Sleeper's Robe

Enchant creature
Enchanted creature has fear. (It can't be blocked except by artifact creatures and/or black creatures.)
Whenever enchanted creature deals combat damage to an opponent, you may draw a card.

Norritt

{T}: Untap target blue creature.
{T}: Choose target non-Wall creature the active player has controlled continuously since the beginning of the turn. That creature attacks this turn if able. Destroy it at the beginning of the next end step if it didn't attack this turn. Activate only before attackers are declared.

Dimir Signet

Quickchange

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

Azorius Aethermage

Whenever a permanent is returned to your hand, you may pay {1}. If you do, draw a card.

Generous Gift

Destroy target permanent. Its controller creates a 3/3 green Elephant creature token.

Perish

Destroy all green creatures. They can't be regenerated.

Grand Arbiter Augustin IV

White spells you cast cost {1} less to cast.
Blue spells you cast cost {1} less to cast.
Spells your opponents cast cost {1} more to cast.

Alchor's Tomb

{2}, {T}: Target permanent you control becomes the color of your choice. (This effect lasts indefinitely.)

Scuttlemutt

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

Insight

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

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.)

Arcane Signet

Ashiok, Nightmare Muse

+1: Create a 2/3 blue and black Nightmare creature token with "Whenever this creature attacks or blocks, each opponent exiles the top two cards of their library."
−3: Return target nonland permanent to its owner's hand, then that player exiles a card from their hand.
−7: You may cast up to three spells from among face-up cards your opponents own from exile without paying their mana costs.

Anguished Unmaking

Exile target nonland permanent. You lose 3 life.

Hydroblast

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

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.

Dream Coat

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

Ersatz Gnomes

{T}: Target spell becomes colorless.
{T}: Target permanent becomes colorless until end of turn.