Solve the Equation

Search your library for an instant or sorcery card, reveal it, put it into your hand, then shuffle.

Wash Away

Cleave {1}{U}{U} (You may cast this spell for its cleave cost. If you do, remove the words in square brackets.)
Counter target spell [that wasn't cast from its owner's hand].

Spell Pierce

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

Curse of the Swine

Exile X target creatures. For each creature exiled this way, its controller creates a 2/2 green Boar creature token.

Wavebreak Hippocamp

Whenever you cast your first spell during each opponent's turn, draw a card.

Disallow

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

Wizard's Retort

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

Vapor Snag

Return target creature to its owner's hand. Its controller loses 1 life.

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.

Wizards of Thay

Myriad (Whenever this creature attacks, for each opponent other than defending player, you may create a token copy that's tapped and attacking that player or a planeswalker they control. Exile the tokens at end of combat.)
Instant and sorcery spells you cast cost {1} less to cast.
You may cast sorcery spells as though they had flash.

Brainstorm

Draw three cards, then put two cards from your hand on top of your library in any order.

Guile

This creature can't be blocked except by three or more creatures.
If a spell or ability you control would counter a spell, instead exile that spell and you may play that card without paying its mana cost.
When Guile is put into a graveyard from anywhere, shuffle it into its owner's library.

Rewind

Counter target spell. Untap up to four lands.

Baral, Chief of Compliance

Instant and sorcery spells you cast cost {1} less to cast.
Whenever a spell or ability you control counters a spell, you may draw a card. If you do, discard a card.

Sinister Sabotage

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

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 this creature: 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

Ponder

Look at the top three cards of your library, then put them back in any order. You may shuffle.
Draw a card.

Windfall

Each player discards their hand, then draws cards equal to the greatest number of cards a player discarded this way.

Temple of the False God

{T}: Add {C}{C}. Activate only if you control five or more lands.

Haughty Djinn

Flying
Haughty Djinn's power is equal to the number of instant and sorcery cards in your graveyard.
Instant and sorcery spells you cast cost {1} less to cast.

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.

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.

Neutralize

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

Ertai's Scorn

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

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.

Final Iteration

Flying
Wizards you control get +2/+1 and have flying.
Whenever you cast an instant or sorcery spell, create a 1/1 blue Human Wizard creature token.

Docent of Perfection

Flying
Whenever you cast an instant or sorcery spell, create a 1/1 blue Human Wizard creature token. Then if you control three or more Wizards, transform this creature.

Docent of Perfection // Final Iteration

Dramatic Reversal

Untap all nonland permanents you control.

String of Disappearances

Return target creature to its owner's hand. Then that creature's controller may pay {U}{U}. If the player does, they may copy this spell and may choose a new target for that copy.

Library of Leng

You have no maximum hand size.
If an effect causes you to discard a card, discard it, but you may put it on top of your library instead of into your graveyard.

Counterspell

Long-Term Plans

Search your library for a card, then shuffle and put that card third from the top.

Arcane Signet

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

Negate

Dissolve

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

Disdainful Stroke

Counter target spell with mana value 4 or greater.

Unwind

Counter target noncreature spell. Untap up to three lands.

Unsummon

Return target creature to its owner's hand.

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.

Island

Pongify

Destroy target creature. It can't be regenerated. Its controller creates a 3/3 green Ape creature token.

Soul Read

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

Void Shatter

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

Tale's End

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

Mana Leak

Counter target spell unless its controller pays {3}.

Drown in Shapelessness

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.

Dissipate

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

Parallel Thoughts

When this enchantment enters, search your library for seven cards, exile them in a face-down pile, and shuffle that pile. Then shuffle your library.
If you would draw a card, you may instead put the top card of the pile you exiled into your hand.

Archmage Emeritus

Magecraft — Whenever you cast or copy an instant or sorcery spell, 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 token: Add one mana of any color.")

Cancel

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.)

Leyline of Anticipation

If this card is in your opening hand, you may begin the game with it on the battlefield.
You may cast spells as though they had flash.

Sky Diamond

This artifact enters tapped.
{T}: Add {U}.

Dispel

Rapid Hybridization

Destroy target creature. It can't be regenerated. That creature's controller creates a 3/3 green Frog Lizard creature token.

Preordain

Scry 2, then draw a card. (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.)

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.")

Rhystic Study

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

Bane's Contingency

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

Naiad of Hidden Coves

During turns other than yours, spells you cast cost {1} less to cast.

Defabricate

Choose one —
• Counter target artifact or enchantment spell. If a spell is countered this way, exile it instead of putting it into its owner's graveyard.
• Counter target activated or triggered ability.

You Find the Villains' Lair

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

Talrand, Sky Summoner

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

Fading Hope

Return target creature to its owner's hand. If its mana value was 3 or less, scry 1. (Look at the top card of your library. You may put that card on the bottom.)

Reality Shift

Exile target creature. Its controller manifests the top card of their library. (That player puts the top card of their library onto the battlefield face down as a 2/2 creature. If it's a creature card, it can be turned face up any time for its mana cost.)

Dismiss

Essence Scatter

Sol Ring

Murmuring Mystic

Whenever you cast an instant or sorcery spell, create a 1/1 blue Bird Illusion creature token with flying.