Fierce Guardianship

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

Annul

Counter target artifact or enchantment spell.

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.

False Summoning

Jwari Ruins

Jwari Disruption

Counter target spell unless its controller pays {1}.

Jwari Disruption // Jwari Ruins

Thought Collapse

Counter target spell. Its controller mills three cards.

Three Steps Ahead

Spree (Choose one or more additional costs.)
+ {1}{U} — Counter target spell.
+ {3} — Create a token that's a copy of target artifact or creature you control.
+ {2} — Draw two cards, then discard a card.

Condescend

Counter target spell unless its controller pays {X}. 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.)

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.

Hinder

Counter target spell. If that spell is countered this way, put that card on your choice of the top or bottom of its owner's library instead of into that player's graveyard.

An Offer You Can't Refuse

Counter target noncreature spell. Its controller creates two Treasure tokens. (They're artifacts with "{T}, Sacrifice this token: Add one mana of any color.")

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.

Complicate

Counter target spell unless its controller pays {3}.
Cycling {2}{U} ({2}{U}, Discard this card: Draw a card.)
When you cycle this card, you may counter target spell unless its controller pays {1}.

Preemptive Strike

Didn't Say Please

Sunken Field

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

Censor

Counter target spell unless its controller pays {1}.
Cycling {U} ({U}, Discard this card: 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}.

Consign to Memory

Replicate {1} (When you cast this spell, copy it for each time you paid its replicate cost. You may choose new targets for the copies.)
Counter target triggered ability or colorless spell.

Force Spike

Overwhelming Denial

Surge {U}{U} (You may cast this spell for its surge cost if you or a teammate has cast another spell this turn.)
This spell can't be countered.
Counter target spell.

Disallow

Counter target spell, activated ability, or triggered ability. (Mana abilities can't be targeted.)

Evasive Action

Domain — Counter target spell unless its controller pays {1} for each basic land type among lands you control.

Flare of Denial

You may sacrifice a nontoken blue creature rather than pay this spell's mana cost.
Counter target spell.

Intervene

Counter target spell that targets a creature.

Dispel

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}.

Squelch

Counter target activated ability. (Mana abilities can't be targeted.)
Draw a card.

Tale's End

Counter target activated ability, triggered ability, or legendary spell.

Teferi's Response

Counter target spell or ability an opponent controls that targets a land you control. If a permanent's ability is countered this way, destroy that permanent.
Draw two cards.

Spell Syphon

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

Disrupt

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

Wizard's Retort

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

Abjure

As an additional cost to cast this spell, sacrifice a blue permanent.
Counter target spell.

Ring of Immortals

{3}, {T}: Counter target instant or Aura spell that targets a permanent you control.

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.

Miscalculation

Counter target spell unless its controller pays {2}.
Cycling {2} ({2}, Discard this card: 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.

Counterspell

Unwind

Counter target noncreature spell. Untap up to three lands.

Deprive

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

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.)

Out of Bounds

Assist (Another player can pay up to {3} of this spell's cost.)
Counter target spell.

Cryptic Command

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

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.)

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.

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.

Misdirection

You may exile a blue card from your hand rather than pay this spell's mana cost.
Change the target of target spell with a single target.

Rewind

Counter target spell. Untap up to four lands.

Common Courtesy

Whenever a player casts a spell without asking your permission while casting it, counter that spell.
When a player asks you permission to cast a spell and you refuse, counter that spell and sacrifice this enchantment.

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.

Stifle

Counter target activated or triggered ability. (Mana abilities can't be targeted.)

Negate

Miscast

Counter target instant or sorcery spell unless its controller pays {3}.

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.