Well-Laid Plans

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

Propaganda

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

Reliquary Tower

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

Vedalken Plotter

When Vedalken Plotter enters, exchange control of target land you control and target land an opponent controls.

King Crab

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

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}

Voidmage Prodigy

{U}{U}, Sacrifice a Wizard: Counter target spell.
Morph {U} (You may cast this card face down as a 2/2 creature for {3}. Turn it face up any time for its morph cost.)

Blind Seer

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

Eluge, the Shoreless Sea

Eluge's power and toughness are each equal to the number of Islands you control.
Whenever Eluge enters or attacks, put a flood counter on target land. It's an Island in addition to its other types for as long as it has a flood counter on it.
The first instant or sorcery spell you cast each turn costs {U} (or {1}) less to cast for each land you control with a flood counter on it.

Arcane Signet

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

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.

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.

Sunken Field

Enchant land
Enchanted land has "{T}: Counter target spell unless its controller pays {1}."

Thassa's Oracle

When Thassa's Oracle enters, look at the top X cards of your library, where X is your devotion to blue. Put up to one of them on top of your library and the rest on the bottom of your library in a random order. If X is greater than or equal to the number of cards in your library, you win the game. (Each {U} in the mana costs of permanents you control counts toward your devotion to blue.)

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.

Sky Diamond

Azami, Lady of Scrolls

Tap an untapped Wizard you control: Draw a card.

Impulse

Look at the top four cards of your library. Put one of them into your hand and the rest on the bottom of your library in any order.

Douse

Thought Vessel

Winged Boots

Equipped creature has flying and ward {4}. (Whenever equipped creature becomes the target of a spell or ability an opponent controls, counter it unless that player pays {4}.)
Equip {1}

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.)

Counterspell

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.

Hibernation

Return all green permanents to their owners' hands.

Step Through

Return two target creatures to their owners' hands.
Wizardcycling {2} ({2}, Discard this card: Search your library for a Wizard card, reveal it, put it into your hand, then shuffle.)

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.

Negate

Burnished Hart

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

Riptide

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."

Scuttlemutt

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

Wash Out

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

Blue Elemental Blast

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

Hydroblast

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

Words of Wind

{1}: The next time you would draw a card this turn, each player returns a permanent they control to its owner's hand instead.

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.

Temple of the False God

{T}: Add {C}{C}. Activate only if you control five or more lands.

Sinister Concierge

When Sinister Concierge dies, you may exile it and put three time counters on it. If you do, exile up to one target creature and put three time counters on it. Each card exiled this way that doesn't have suspend gains suspend. (For each card with suspend, its owner removes a time counter from it at the beginning of their upkeep. When the last is removed, they may cast it without paying its mana cost. Those creature spells have haste.)

Curate

Surveil 2. (Look at the top two cards of your library, then put any number of them into your graveyard and the rest on top of your library in any order.)
Draw a card.

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.

Minor Misstep

Counter target spell with mana value 1 or less.

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}

Sisay's Ingenuity

Enchant creature
When Sisay's Ingenuity enters, draw a card.
Enchanted creature has "{2}{U}: Target creature becomes the color of your choice until end of turn."

Fatespinner

At the beginning of each opponent's upkeep, that player chooses draw step, main phase, or combat phase. The player skips each instance of the chosen step or phase this turn.

Distorting Lens

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

Benevolent Geist

Flying
Noncreature spells you control can't be countered.
If Benevolent Geist would be put into a graveyard from anywhere, exile it instead.

Malevolent Hermit

{U}, Sacrifice Malevolent Hermit: Counter target noncreature spell unless its controller pays {3}.
Disturb {2}{U} (You may cast this card from your graveyard transformed for its disturb cost.)

Malevolent Hermit // Benevolent Geist

Pongify

Destroy target creature. It can't be regenerated. Its controller creates a 3/3 green Ape creature token.

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.

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.

Defiler of Dreams

Flying
As an additional cost to cast blue permanent spells, you may pay 2 life. Those spells cost {U} less to cast if you paid life this way. This effect reduces only the amount of blue mana you pay.
Whenever you cast a blue permanent spell, draw a card.

Shell Skulkin

{3}: Target blue creature gains shroud until end of turn. (It can't be the target of spells or abilities.)

Change the Equation

Choose one —
• Counter target spell with mana value 2 or less.
• Counter target red or green spell with mana value 6 or less.

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.

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.)

High Tide

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

Information Dealer

{T}: Look at the top X cards of your library, where X is the number of Wizards on the battlefield, then put them back in any order.

Lonely Sandbar

Lonely Sandbar enters tapped.
{T}: Add {U}.
Cycling {U} ({U}, Discard this card: Draw a card.)

Sea Sprite

Duelist of the Mind

Flying, vigilance
Duelist of the Mind's power is equal to the number of cards you've drawn this turn.
Whenever you commit a crime, you may draw a card. If you do, discard a card. This ability triggers only once each turn.

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.

Tidal Visionary

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

Flash Flood

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

Wizard's Retort

This spell costs {1} less to cast if you control a Wizard.
Counter target spell.

Sol Ring

Fellwar Stone

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

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.

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.

Kasmina, Enigmatic Mentor

Spells your opponents cast that target a creature or planeswalker you control cost {2} more to cast.
−2: Create a 2/2 blue Wizard creature token. Draw a card, then discard 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.

Dramatic Reversal

Untap all nonland permanents you control.

Gainsay

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.

Stormtide Leviathan

Islandwalk (This creature can't be blocked as long as defending player controls an Island.)
All lands are Islands in addition to their other types.
Creatures without flying or islandwalk can't attack.

Siren Stormtamer

Flying
{U}, Sacrifice Siren Stormtamer: Counter target spell or ability that targets you or a creature you control.

Sway of Illusion

Any number of target creatures become the color of your choice until end of turn.
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.)

Valley Floodcaller

Flash
You may cast noncreature spells as though they had flash.
Whenever you cast a noncreature spell, Birds, Frogs, Otters, and Rats you control get +1/+1 until end of turn. Untap them.

The Reality Chip

You may look at the top card of your library any time.
As long as The Reality Chip is attached to a creature, you may play lands and cast spells from the top of your library.
Reconfigure {2}{U} ({2}{U}: Attach to target creature you control; or unattach from a creature. Reconfigure only as a sorcery. While attached, this isn't a creature.)

Halimar Depths

Halimar Depths enters tapped.
When Halimar Depths enters, look at the top three cards of your library, then put them back in any order.
{T}: Add {U}.

The Flood of Mars

Islandwalk (This creature can't be blocked as long as defending player controls an Island.)
Water Always Wins — Whenever The Flood of Mars attacks, put a flood counter on another target creature or land. If it's a creature, it becomes a copy of The Flood of Mars. If it's a land, it becomes an Island in addition to its other types.

Rapid Hybridization

Destroy target creature. It can't be regenerated. That creature's controller creates a 3/3 green Frog Lizard creature token.

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.

Sapphire Medallion

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

Flashfreeze

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.

Inundate

Return all nonblue creatures to their owners' hands.

Liquimetal Torque

{T}: Add {C}.
{T}: Target nonland permanent becomes an artifact in addition to its other types until end of turn.

Jaded Response

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

Psychic Battle

Whenever a player chooses one or more targets, each player reveals the top card of their library. The player who reveals the card with the highest mana value may change the target or targets. If two or more cards are tied for highest, the target or targets remain unchanged. Changing targets this way doesn't trigger abilities of permanents named Psychic Battle.

Archaeomancer

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

Hidden Cataract

Hidden Cataract enters tapped.
{T}: Add {U}.
{4}{U}, {T}, Sacrifice Hidden Cataract: Discover 4. Activate only as a sorcery. (Exile cards from the top of your library until you exile a nonland card with mana value 4 or less. Cast it without paying its mana cost or put it into your hand. Put the rest on the bottom in a random order.)

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.

Patron Wizard

Tap an untapped Wizard you control: Counter target spell unless its controller pays {1}.

Skill Borrower

Play with the top card of your library revealed.
As long as the top card of your library is an artifact or creature card, Skill Borrower has all activated abilities of that card. (If any of the abilities use that card's name, use this creature's name instead.)

Shifting Sky

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

Harbinger of the Seas

Imagecrafter

{T}: Choose a creature type other than Wall. Target creature becomes that type until end of turn.

Baral, Chief of Compliance

Instant and sorcery spells you cast cost {1} less to cast.
Whenever a spell or ability you control counters a spell, you may draw a card. If you do, discard a card.

Terrain Generator

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