Disdainful Stroke

Counter target spell with mana value 4 or greater.

Stronghold Biologist

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

Spell Blast

Counter target spell with mana value X. (For example, if that spell's mana cost is {3}{U}{U}, X is 5.)

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.)

Scatter Arc

Counter target noncreature spell.
Draw a card.

False Summoning

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.

Contradict

Dissolve

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

Counterspell

Familiar's Ruse

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

Daring Apprentice

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

Logic Knot

Delve (Each card you exile from your graveyard while casting this spell pays for {1}.)
Counter target spell unless its controller pays {X}.

Foil

You may discard an Island card and another card rather than pay this spell's mana cost.
Counter target spell.

Rewind

Counter target spell. Untap up to four lands.

Put Away

Counter target spell. You may shuffle up to one target card from your graveyard into your library.

Second Guess

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

Abjure

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

Nullify

Last Word

This spell can't be countered.
Counter target spell.

Ertai, Wizard Adept

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.)

Overwhelming Intellect

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

Remove Soul

Stronghold Machinist

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

Preemptive Strike

Staff of Nin

At the beginning of your upkeep, draw a card.
{T}: Staff of Nin deals 1 damage to any target.

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.

Dismal Failure

Counter target spell. Its controller discards a card.

Wall of Frost

Defender
Whenever Wall of Frost blocks a creature, that creature doesn't untap during its controller's next untap step.

Summoner's Bane

Counter target creature spell. Create a 2/2 blue Illusion creature token.

Counter target spell. That spell's controller may draw a card.

Kheru Spellsnatcher

Morph {4}{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 Kheru Spellsnatcher is turned face up, counter target spell. If that spell is countered this way, exile it instead of putting it into its owner's graveyard. You may cast that card without paying its mana cost for as long as it remains exiled.

Lay Bare

Counter target spell. Look at its controller's hand.

Exclude

Counter target creature spell.
Draw a card.

Discombobulate

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

Countermand

Counter target spell. Its controller mills four cards.

Realmwright

As Realmwright enters, choose a basic land type.
Lands you control are the chosen type in addition to their other types.

Scroll of the Masters

Whenever you cast a noncreature spell, put a lore counter on Scroll of the Masters.
{3}, {T}: Target creature you control gets +1/+1 until end of turn for each lore counter on Scroll of the Masters.

Dream Fracture

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

Faerie Trickery

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

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.

Island

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.

Deprive

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

Negate

Dismiss

Fervent Denial

Counter target spell.
Flashback {5}{U}{U} (You may cast this card from your graveyard for its flashback cost. Then exile it.)

Dissipate

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

Cancel

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.

Controvert

Counter target spell.
Recover {2}{U}{U} (When a creature is put into your graveyard from the battlefield, you may pay {2}{U}{U}. If you do, return this card from your graveyard to your hand. Otherwise, exile this 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.

Geist Snatch

Counter target creature spell. Create a 1/1 blue Spirit creature token with flying.

Mystic Denial

Counter target creature or sorcery spell.

Declaration of Naught

As Declaration of Naught enters, choose a card name.
{U}: Counter target spell with the chosen name.

Essence Scatter

Bone to Ash

Fuel for the Cause

Counter target spell, then proliferate. (Choose any number of permanents and/or players, then give each another counter of each kind already there.)

Stoic Rebuttal

Metalcraft — This spell costs {1} less to cast if you control three or more artifacts.
Counter target spell.

Psychic Barrier

Counter target creature spell. Its controller loses 1 life.

Annul

Counter target artifact or enchantment spell.

Sphinx-Bone Wand

Whenever you cast an instant or sorcery spell, you may put a charge counter on Sphinx-Bone Wand. If you do, Sphinx-Bone Wand deals damage equal to the number of charge counters on it to any target.