Hullbreaker Horror

Flash
This spell can't be countered.
Whenever you cast a spell, choose up to one —
• Return target spell you don't control to its owner's hand.
• Return target nonland permanent to its owner's hand.

In the Eye of Chaos

Whenever a player casts an instant spell, counter it unless that player pays {X}, where X is its mana value.

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.)

Fierce Guardianship

If you control a commander, you may cast this spell without paying its mana cost.
Counter target noncreature spell.

Time Warp

Target player takes an extra turn after this one.

Dispel

Castle Vantress

Castle Vantress enters tapped unless you control an Island.
{T}: Add {U}.
{2}{U}{U}, {T}: Scry 2.

Reliquary Tower

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

Thriving Isle

Thriving Isle enters tapped. As it enters, choose a color other than blue.
{T}: Add {U} or one mana of the chosen color.

Smokestack

At the beginning of your upkeep, you may put a soot counter on Smokestack.
At the beginning of each player's upkeep, that player sacrifices a permanent of their choice for each soot counter on Smokestack.

Winter Moon

Players can't untap more than one nonbasic land during their untap steps.

Urza, Lord High Artificer

When Urza, Lord High Artificer enters, create a 0/0 colorless Construct artifact creature token with "This creature gets +1/+1 for each artifact you control."
Tap an untapped artifact you control: Add {U}.
{5}: Shuffle your library, then exile the top card. Until end of turn, you may play that card without paying its mana cost.

Jin-Gitaxias, Progress Tyrant

Whenever you cast an artifact, instant, or sorcery spell, copy that spell. You may choose new targets for the copy. This ability triggers only once each turn. (A copy of a permanent spell becomes a token.)
Whenever an opponent casts an artifact, instant, or sorcery spell, counter that spell. This ability triggers only once each turn.

Temporal Manipulation

Timesifter

At the beginning of each upkeep, each player exiles the top card of their library. The player who exiled the card with the highest mana value takes an extra turn after this one. If two or more players' cards are tied for highest, the tied players repeat this process until the tie is broken.

Stasis

Players skip their untap steps.
At the beginning of your upkeep, sacrifice Stasis unless you pay {U}.

The Tabernacle at Pendrell Vale

All creatures have "At the beginning of your upkeep, destroy this creature unless you pay {1}."

Rhystic Study

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

Thought Vessel

Temporal Mastery

Take an extra turn after this one. Exile Temporal Mastery.
Miracle {1}{U} (You may cast this card for its miracle cost when you draw it if it's the first card you drew this turn.)

Consecrated Sphinx

Flying
Whenever an opponent draws a card, you may draw two cards.

Island

Pact of Negation

Counter target spell.
At the beginning of your next upkeep, pay {3}{U}{U}. If you don't, you lose the game.

Narset, Parter of Veils

Each opponent can't draw more than one card each turn.
−2: Look at the top four cards of your library. You may reveal a noncreature, nonland card from among them and put it into your hand. Put the rest on the bottom of your library in a random order.

Static Orb

As long as Static Orb is untapped, players can't untap more than two permanents during their untap steps.

Force of Negation

If it's not your turn, you may exile a blue card from your hand rather than pay this spell's mana cost.
Counter target noncreature spell. If that spell is countered this way, exile it instead of putting it into its owner's graveyard.

Arcane Laboratory

Each player can't cast more than one spell each turn.

Vivid Creek

Vivid Creek enters tapped with two charge counters on it.
{T}: Add {U}.
{T}, Remove a charge counter from Vivid Creek: Add one mana of any color.

Sol Ring

Torpor Orb

Creatures entering don't cause abilities to trigger.

Capture of Jingzhou

Force of Will

You may pay 1 life and exile a blue card from your hand rather than pay this spell's mana cost.
Counter target spell.

Land Equilibrium

If an opponent who controls at least as many lands as you do would put a land onto the battlefield, that player instead puts that land onto the battlefield then sacrifices a land of their choice.

Arcane Signet

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

Platinum Angel

Flying
You can't lose the game and your opponents can't win the game.

Skyline Cascade

Skyline Cascade enters tapped.
When Skyline Cascade enters, target creature an opponent controls doesn't untap during its controller's next untap step.
{T}: Add {U}.

Trinisphere

As long as Trinisphere is untapped, each spell that would cost less than three mana to cast costs three mana to cast. (Additional mana in the cost may be paid with any color of mana or colorless mana. For example, a spell that would cost {1}{B} to cast costs {2}{B} to cast instead.)

Mana Vortex

When you cast this spell, counter it unless you sacrifice a land.
At the beginning of each player's upkeep, that player sacrifices a land of their choice.
When there are no lands on the battlefield, sacrifice Mana Vortex.

Mystical Dispute

This spell costs {2} less to cast if it targets a blue spell.
Counter target spell unless its controller pays {3}.

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.")

Overburden

Whenever a player puts a nontoken creature onto the battlefield, that player returns a land they control to its owner's hand.

Platinum Emperion

Your life total can't change. (You can't gain or lose life. You can't pay any amount of life except 0.)

Jin-Gitaxias, Core Augur

Flash
At the beginning of your end step, draw seven cards.
Each opponent's maximum hand size is reduced by seven.

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.

Flusterstorm

Counter target instant or sorcery spell unless its controller pays {1}.
Storm (When you cast this spell, copy it for each spell cast before it this turn. You may choose new targets for the copies.)

Gilded Lotus

Omniscience

You may cast spells from your hand without paying their mana costs.

Counterspell

Sea Gate

Sea Gate enters tapped.
As Sea Gate enters, choose a color other than blue.
{T}: Add {U} or one mana of the chosen color.

Remote Isle

Remote Isle enters tapped.
{T}: Add {U}.
Cycling {2} ({2}, Discard this card: Draw a card.)

The One Ring

Indestructible
When The One Ring enters, if you cast it, you gain protection from everything until your next turn.
At the beginning of your upkeep, you lose 1 life for each burden counter on The One Ring.
{T}: Put a burden counter on The One Ring, then draw a card for each burden counter on The One Ring.

Embargo

Nonland permanents don't untap during their controllers' untap steps.
At the beginning of your upkeep, you lose 2 life.

Time Stretch

Target player takes two extra turns after this one.

Midnight Clock

{T}: Add {U}.
{2}{U}: Put an hour counter on Midnight Clock.
At the beginning of each upkeep, put an hour counter on Midnight Clock.
When the twelfth hour counter is put on Midnight Clock, shuffle your hand and graveyard into your library, then draw seven cards. Exile Midnight Clock.

Nexus of Fate

Take an extra turn after this one.
If Nexus of Fate would be put into a graveyard from anywhere, reveal Nexus of Fate and shuffle it into its owner's library instead.

Commander's Sphere

{T}: Add one mana of any color in your commander's color identity.
Sacrifice Commander's Sphere: Draw a card.

Swan Song

Counter target enchantment, instant, or sorcery spell. Its controller creates a 2/2 blue Bird creature token with flying.

Sunder

Blightsteel Colossus

Trample, infect, indestructible
If Blightsteel Colossus would be put into a graveyard from anywhere, reveal Blightsteel Colossus and shuffle it into its owner's library instead.

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}.

Mindslaver

{4}, {T}, Sacrifice Mindslaver: You control target player during that player's next turn. (You see all cards that player could see and make all decisions for the player.)

Mana Drain

Counter target spell. At the beginning of your next main phase, add an amount of {C} equal to that spell's mana value.

Winter Orb

As long as Winter Orb is untapped, players can't untap more than one land during their untap steps.

Mind Stone

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

Sapphire Medallion

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

Cryptic Command

Choose two —
• Counter target spell.
• Return target permanent to its owner's hand.
• Tap all creatures your opponents control.
• Draw a card.

Daze

You may return an Island you control to its owner's hand rather than pay this spell's mana cost.
Counter target spell unless its controller pays {1}.

Rising Waters

Lands don't untap during their controllers' untap steps.
At the beginning of each player's upkeep, that player untaps a land they control.

Mana Breach

Whenever a player casts a spell, that player returns a land they control to its owner's hand.

Portal to Phyrexia

When Portal to Phyrexia enters, each opponent sacrifices three creatures of their choice.
At the beginning of your upkeep, put target creature card from a graveyard onto the battlefield under your control. It's a Phyrexian in addition to its other types.

Coldsteel Heart

Coldsteel Heart enters tapped.
As Coldsteel Heart enters, choose a color.
{T}: Add one mana of the chosen color.