Access Denied

Counter target spell. Create X 1/1 colorless Thopter artifact creature tokens with flying, where X is that spell's mana value.

Didn't Say Please

Counter target spell. Its controller mills three cards.

Keep Safe

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

Hindering Touch

Counter target spell unless its controller pays {2}.
Storm (When you cast this spell, copy it for each spell cast before it this turn. You may choose new targets for the copies.)

Forceful Denial

Cascade (When you cast this spell, exile cards from the top of your library until you exile a nonland card that costs less. You may cast it without paying its mana cost. Put the exiled cards on the bottom in a random order.)
Counter target spell.

Annul

Counter target artifact or enchantment spell.

Bane's Contingency

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

Bone to Ash

Counter target creature spell.
Draw a card.

Brine Seer

{2}{U}, {T}: Reveal any number of blue cards in your hand. Counter target spell unless its controller pays {1} for each card revealed this way.

Dissipate

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

Discombobulate

Counter target spell. Look at the top four cards of your library, then put them back in any order.

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.

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.

Talrand, Sky Summoner

Whenever you cast an instant or sorcery spell, create a 2/2 blue Drake creature token with flying.

Hisoka, Minamo Sensei

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

Counterbore

Counter target spell. Search its controller's graveyard, hand, and library for all cards with the same name as that spell and exile them. Then that player shuffles.

Flashfreeze

Circular Logic

Counter target spell unless its controller pays {1} for each card in your graveyard.
Madness {U} (If you discard this card, discard it into exile. When you do, cast it for its madness cost or put it into your graveyard.)

Envelop

Blue Elemental Blast

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

Confound

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

An Offer You Can't Refuse

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

Dream Fracture

Counter target spell. Its controller draws a card.
Draw a card.

Counterspell

Cancel

Essence Scatter

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.)

Countermand

Counter target spell. Its controller mills four cards.

Dispel

Deny the Divine

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

Counterlash

Counter target spell. You may cast a spell that shares a card type with it from your hand without paying its mana cost.

Disallow

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

Decree of Silence

Whenever an opponent casts a spell, counter that spell and put a depletion counter on Decree of Silence. If there are three or more depletion counters on Decree of Silence, sacrifice it.
Cycling {4}{U}{U} ({4}{U}{U}, Discard this card: Draw a card.)
When you cycle Decree of Silence, you may 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.")

Deprive

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