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.

Annul

Counter target artifact or enchantment spell.

Overcharged Amalgam

Flash
Flying
Exploit (When this creature enters, you may sacrifice a creature.)
When Overcharged Amalgam exploits a creature, counter target spell, activated ability, or triggered ability.

Remand

Counter target spell. If that spell is countered this way, put it into its owner's hand instead of into that player's graveyard.
Draw a card.

Minor Misstep

Counter target spell with mana value 1 or less.

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.

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.

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.

Rewind

Counter target spell. Untap up to four lands.

Muddle the Mixture

Counter target instant or sorcery spell.
Transmute {1}{U}{U} ({1}{U}{U}, Discard this card: Search your library for a card with the same mana value as this card, reveal it, put it into your hand, then shuffle. Transmute only as a sorcery.)

Dissipate

Counter target spell. If that spell is countered this way, exile it instead of putting it into its owner's graveyard.

Runeboggle

Counter target spell unless its controller pays {1}.
Draw a card.

Bring the Ending

Counter target spell unless its controller pays {2}.
Corrupted — Counter that spell instead if its controller has three or more poison counters.

Saw It Coming

Counter target spell.
Foretell {1}{U} (During your turn, you may pay {2} and exile this card from your hand face down. Cast it on a later turn for its foretell cost.)

Deprive

As an additional cost to cast this spell, return a land you control to its owner's hand.
Counter target spell.

Neutralizing Blast

Stern Scolding

Counter target creature spell with power or toughness 2 or less.

Wizard's Retort

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

Essence Scatter

Outwit

Counter target spell that targets a player.

Lofty Denial

Counter target spell unless its controller pays {1}. If you control a creature with flying, counter that spell unless its controller pays {4} instead.

Interdict

Counter target activated ability from an artifact, creature, enchantment, or land. That permanent's activated abilities can't be activated this turn. (Mana abilities can't be targeted.)
Draw a card.

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.

Thassa's Rebuff

Counter target spell unless its controller pays {X}, where X is your devotion to blue. (Each {U} in the mana costs of permanents you control counts toward your devotion to blue.)

Concerted Defense

Counter target noncreature spell unless its controller pays {1} plus an additional {1} for each creature in your party. (Your party consists of up to one each of Cleric, Rogue, Warrior, and Wizard.)

Extinguish

Spell Snare

Siren Stormtamer

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

Ertai, Wizard Adept

Sublime Epiphany

Choose one or more —
• Counter target spell.
• Counter target activated or triggered ability.
• Return target nonland permanent to its owner's hand.
• Create a token that's a copy of target creature you control.
• Target player draws a card.

Stronghold Biologist

{U}{U}, {T}, Discard a card: Counter target creature spell.

Force Spike

Counter target spell unless its controller pays {1}.

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.)

Horribly Awry

Devoid (This card has no color.)
Counter target creature spell with mana value 4 or less. If that spell is countered this way, exile it instead of putting it into its owner's graveyard.

Unwind

Counter target noncreature spell. Untap up to three lands.

Daring Apprentice

{T}, Sacrifice Daring Apprentice: Counter target spell.

Mausoleum Wanderer

Flying
Whenever another Spirit you control enters, Mausoleum Wanderer gets +1/+1 until end of turn.
Sacrifice Mausoleum Wanderer: Counter target instant or sorcery spell unless its controller pays {X}, where X is Mausoleum Wanderer's power.

Silumgar Spell-Eater

Megamorph {4}{U} (You may cast this card face down as a 2/2 creature for {3}. Turn it face up any time for its megamorph cost and put a +1/+1 counter on it.)
When Silumgar Spell-Eater is turned face up, counter target spell unless its controller pays {3}.

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}.

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

Dissolve

Counter target spell. Scry 1. (Look at the top card of your library. You may put that card on the bottom.)

Insidious Will

Choose one —
• Counter target spell.
• You may choose new targets for target spell.
• Copy target instant or sorcery spell. You may choose new targets for the copy.

Soratami Savant

Flying
{3}, Return a land you control to its owner's hand: Counter target spell unless its controller pays {3}.

Make Disappear

Casualty 1 (As you cast this spell, you may sacrifice a creature with power 1 or greater. When you do, copy this spell and you may choose a new target for the copy.)
Counter target spell unless its controller pays {2}.

Reject

Counter target creature or planeswalker spell unless its controller pays {3}. If that spell is countered this way, exile it instead of putting it into its owner's graveyard.

You Find the Villains' Lair

Choose one —
• Foil Their Scheme — Counter target spell.
• Learn Their Secrets — Draw two cards, then discard two cards.

Spell Syphon

Counter target spell unless its controller pays {1} for each blue permanent you control.

Familiar's Ruse

As an additional cost to cast this spell, return a creature you control to its owner's hand.
Counter target spell.

Mana Leak

Counter target spell unless its controller pays {3}.

Cursecatcher

Sacrifice Cursecatcher: Counter target instant or sorcery spell unless its controller pays {1}.

Confound

Counter target spell that targets a creature.
Draw a card.

Mystical Dispute

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

Lilting Refrain

At the beginning of your upkeep, you may put a verse counter on Lilting Refrain.
Sacrifice Lilting Refrain: Counter target spell unless its controller pays {X}, where X is the number of verse counters on Lilting Refrain.

Keep Safe

Counter target spell that targets a permanent you control.
Draw a card.

Neutralize

Counter target spell.
Cycling {2} ({2}, Discard this card: Draw a card.)

Lullmage Mentor

Whenever a spell or ability you control counters a spell, you may create a 1/1 blue Merfolk creature token.
Tap seven untapped Merfolk you control: Counter target spell.

Deny Existence

Counter target creature spell. If that spell is countered this way, exile it instead of putting it into its owner's graveyard.

Anticognition

Counter target creature or planeswalker spell unless its controller pays {2}. If an opponent has eight or more cards in their graveyard, instead counter that spell, then scry 2.

Calculated Dismissal

Counter target spell unless its controller pays {3}.
Spell mastery — If there are two or more instant and/or sorcery cards in your graveyard, scry 2. (To scry 2, look at the top two cards of your library, then put any number of them on the bottom and the rest on top in any order.)

Hisoka, Minamo Sensei

{2}{U}, Discard a card: Counter target spell if it has the same mana value as the discarded card.

Disruption Protocol

As an additional cost to cast this spell, tap an untapped artifact you control or pay {1}.
Counter target spell.

Confirm Suspicions

Counter target spell.
Investigate three times. (To investigate, create a Clue token. It's an artifact with "{2}, Sacrifice this artifact: Draw a card.")

Envelop

Archmage's Charm

Choose one —
• Counter target spell.
• Target player draws two cards.
• Gain control of target nonland permanent with mana value 1 or less.

Flash Counter

Soul Read

Choose one —
• Counter target spell unless its controller pays {4}.
• Draw two cards.

Spell Pierce

Counter target noncreature spell unless its controller pays {2}.

Draining Whelk

Flash
Flying
When Draining Whelk enters, counter target spell. Put X +1/+1 counters on Draining Whelk, where X is that spell's mana value.

Jace, Unraveler of Secrets

+1: Scry 1, then draw a card.
−2: Return target creature to its owner's hand.
−8: You get an emblem with "Whenever an opponent casts their first spell each turn, counter that spell."

Power Sink

Counter target spell unless its controller pays {X}. If that player doesn't, they tap all lands with mana abilities they control and lose all unspent mana.

Disdainful Stroke

Counter target spell with mana value 4 or greater.

Dispel

Oppressive Will

Counter target spell unless its controller pays {1} for each card in your hand.

Revolutionary Rebuff

Counter target nonartifact spell unless its controller pays {2}.

Disciple of the Ring

{1}, Exile an instant or sorcery card from your graveyard: Choose one —
• Counter target noncreature spell unless its controller pays {2}.
• Disciple of the Ring gets +1/+1 until end of turn.
• Tap target creature.
• Untap target creature.

Mental Misstep

({U/P} can be paid with either {U} or 2 life.)
Counter target spell with mana value 1.

Quench

Counter target spell unless its controller pays {2}.

Mirrorshell Crab

Ward {3} (Whenever this creature becomes the target of a spell or ability an opponent controls, counter it unless that player pays {3}.)
Channel — {2}{U}, Discard Mirrorshell Crab: Counter target spell or ability unless its controller pays {3}.

Stubborn Denial

Counter target noncreature spell unless its controller pays {1}.
Ferocious — If you control a creature with power 4 or greater, counter that spell instead.

Stymied Hopes

Counter target spell unless its controller pays {1}. Scry 1. (Look at the top card of your library. You may put that card on the bottom.)

Nimble Obstructionist

Flash
Flying
Cycling {2}{U} ({2}{U}, Discard this card: Draw a card.)
When you cycle Nimble Obstructionist, counter target activated or triggered ability you don't control.

Spiketail Hatchling

Flying (This creature can't be blocked except by creatures with flying or reach.)
Sacrifice Spiketail Hatchling: Counter target spell unless its controller pays {1}.

Countervailing Winds

Counter target spell unless its controller pays {1} for each card in your graveyard.
Cycling {2} ({2}, Discard this card: Draw a card.)

Voidmage Apprentice

Morph {2}{U}{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.)
When Voidmage Apprentice is turned face up, counter target spell.

Overwhelming Intellect

Counter target creature spell. Draw cards equal to that spell's mana value.

Delay

Counter target spell. If the spell is countered this way, exile it with three time counters on it instead of putting it into its owner's graveyard. If it doesn't have suspend, it gains suspend. (At the beginning of its owner's upkeep, they remove a time counter. When the last is removed, they may play it without paying its mana cost. If it's a creature, it has haste.)

Second Guess

Counter target spell that's the second spell cast this turn.

Ceremonious Rejection

Ertai's Scorn

This spell costs {U} less to cast if an opponent cast two or more spells this turn.
Counter target spell.

Glen Elendra Archmage

Flying
{U}, Sacrifice Glen Elendra Archmage: Counter target noncreature spell.
Persist (When this creature dies, if it had no -1/-1 counters on it, return it to the battlefield under its owner's control with a -1/-1 counter on it.)

Sister of Silence

Flash
Psychic Abomination — When Sister of Silence enters, counter target instant spell, sorcery spell, activated ability, or triggered ability.

Urza's Rebuff

Choose one —
• Counter target spell.
• Tap up to two target creatures.

Stratus Dancer

Flying
Megamorph {1}{U} (You may cast this card face down as a 2/2 creature for {3}. Turn it face up any time for its megamorph cost and put a +1/+1 counter on it.)
When Stratus Dancer is turned face up, counter target instant or sorcery spell.

Lookout's Dispersal

This spell costs {1} less to cast if you control a Pirate.
Counter target spell unless its controller pays {4}.

Remove Soul

Sinister Sabotage

Counter target spell.
Surveil 1. (Look at the top card of your library. You may put it into your graveyard.)

Spell Contortion

Multikicker {1}{U} (You may pay an additional {1}{U} any number of times as you cast this spell.)
Counter target spell unless its controller pays {2}. Draw a card for each time Spell Contortion was kicked.

Scatter Ray

Counter target artifact or creature spell unless its controller pays {4}.

Rune Snag

Counter target spell unless its controller pays {2} plus an additional {2} for each card named Rune Snag in each graveyard.

Convolute

Counter target spell unless its controller pays {4}.

Bane's Contingency

Counter target spell. If that spell targets a commander you control, instead counter that spell, scry 2, then draw a card.

Vodalian Hexcatcher

Flash
Other Merfolk you control get +1/+1.
Sacrifice a Merfolk: Counter target noncreature spell unless its controller pays {1}.

Psychic Barrier

Counter target creature spell. Its controller loses 1 life.

Essence Capture

Counter target creature spell. Put a +1/+1 counter on up to one target creature you control.