Counterspell

Castle Vantress

Castle Vantress enters tapped unless you control an Island.
{T}: Add {U}.
{2}{U}{U}, {T}: Scry 2.

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.

Tamiyo's Journal

At the beginning of your upkeep, investigate. (Create a Clue token. It's an artifact with "{2}, Sacrifice this artifact: Draw a card.")
{T}, Sacrifice three Clues: Search your library for a card, put that card into your hand, then shuffle.

Storm of Saruman

Ward {3}
Whenever you cast your second spell each turn, copy it, except the copy isn't legendary. You may choose new targets for the copy. (A copy of a permanent spell becomes a token.)

Thassa, God of the Sea

Indestructible
As long as your devotion to blue is less than five, Thassa isn't a creature. (Each {U} in the mana costs of permanents you control counts toward your devotion to blue.)
At the beginning of your upkeep, scry 1.
{1}{U}: Target creature you control can't be blocked this turn.

Talrand, Sky Summoner

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

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.)

Karn's Temporal Sundering

(You may cast a legendary sorcery only if you control a legendary creature or planeswalker.)
Target player takes an extra turn after this one. Return up to one target nonland permanent to its owner's hand. Exile Karn's Temporal Sundering.

Clever Impersonator

You may have Clever Impersonator enter as a copy of any nonland permanent on the battlefield.

Bident of Thassa

Whenever a creature you control deals combat damage to a player, you may draw a card.
{1}{U}, {T}: Creatures your opponents control attack this turn if able.

Maze of Ith

{T}: Untap target attacking creature. Prevent all combat damage that would be dealt to and dealt by that creature this turn.

Saheeli's Artistry

Choose one or both —
• Create a token that's a copy of target artifact.
• Create a token that's a copy of target creature, except it's an artifact in addition to its other types.

Arcanis the Omnipotent

{T}: Draw three cards.
{2}{U}{U}: Return Arcanis the Omnipotent to its owner's hand.

Archaeomancer

When Archaeomancer enters, return target instant or sorcery card from your graveyard to your hand.

Finale of Revelation

Draw X cards. If X is 10 or more, instead shuffle your graveyard into your library, draw X cards, untap up to five lands, and you have no maximum hand size for the rest of the game.
Exile Finale of Revelation.

Dissipate

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

Disallow

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

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.

Thought Vessel

You have no maximum hand size.
{T}: Add {C}.

Jace, Telepath Unbound

+1: Up to one target creature gets -2/-0 until your next turn.
−3: You may cast target instant or sorcery card from your graveyard this turn. If that spell would be put into your graveyard, exile it instead.
−9: You get an emblem with "Whenever you cast a spell, target opponent mills five cards."

Jace, Vryn's Prodigy

{T}: Draw a card, then discard a card. If there are five or more cards in your graveyard, exile Jace, Vryn's Prodigy, then return him to the battlefield transformed under his owner's control.

Jace, Vryn's Prodigy // Jace, Telepath Unbound

Consecrated Sphinx

Flying
Whenever an opponent draws a card, you may draw two cards.

God-Eternal Kefnet

Flying
You may reveal the first card you draw each turn as you draw it. Whenever you reveal an instant or sorcery card this way, copy that card and you may cast the copy. That copy costs {2} less to cast.
When God-Eternal Kefnet dies or is put into exile from the battlefield, you may put it into its owner's library third from the top.

Rite of Replication

Kicker {5} (You may pay an additional {5} as you cast this spell.)
Create a token that's a copy of target creature. If this spell was kicked, create five of those tokens instead.

Sol Ring

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.

Stroke of Genius

Monastery Siege

As Monastery Siege enters, choose Khans or Dragons.
• Khans — At the beginning of your draw step, draw an additional card, then discard a card.
• Dragons — Spells your opponents cast that target you or a permanent you control cost {2} more to cast.

Fact or Fiction

Reveal the top five cards of your library. An opponent separates those cards into two piles. Put one pile into your hand and the other into your graveyard.

Commence the Endgame

This spell can't be countered.
Draw two cards, then amass Zombies X, where X is the number of cards in your hand. (Put X +1/+1 counters on an Army you control. It's also a Zombie. If you don't control an Army, create a 0/0 black Zombie Army creature token first.)

Jace, Wielder of Mysteries

If you would draw a card while your library has no cards in it, you win the game instead.
+1: Target player mills two cards. Draw a card.
−8: Draw seven cards. Then if your library has no cards in it, you win the game.

Halimar Depths

Halimar Depths enters tapped.
When Halimar Depths enters, look at the top three cards of your library, then put them back in any order.
{T}: Add {U}.

Beacon of Tomorrows

Target player takes an extra turn after this one. Shuffle Beacon of Tomorrows into its owner's library.

Mystic Speculation

Buyback {2} (You may pay an additional {2} as you cast this spell. If you do, put this card into your hand as it resolves.)
Scry 3. (Look at the top three cards of your library, then put any number of them on the bottom and the rest on top in any order.)

Blatant Thievery

For each opponent, gain control of target permanent that player controls.

Lier, Disciple of the Drowned

Spells can't be countered.
Each instant and sorcery card in your graveyard has flashback. The flashback cost is equal to that card's mana cost.

Drawn from Dreams

Look at the top seven cards of your library. Put two of them into your hand and the rest on the bottom of your library in a random order.

Jace's Sanctum

Instant and sorcery spells you cast cost {1} less to cast.
Whenever you cast an instant or sorcery spell, scry 1.

Ponder

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

Time Warp

Target player takes an extra turn after this one.

Swarm Intelligence

Whenever you cast an instant or sorcery spell, you may copy that spell. You may choose new targets for the copy.

Thran Dynamo

Plea for Power

Will of the council — Starting with you, each player votes for time or knowledge. If time gets more votes, take an extra turn after this one. If knowledge gets more votes or the vote is tied, draw three cards.

Island

Temple of the False God

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

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.

Sensei's Divining Top

{1}: Look at the top three cards of your library, then put them back in any order.
{T}: Draw a card, then put Sensei's Divining Top on top of its owner's library.

Mind's Desire

Shuffle your library. Then exile the top card of your library. Until end of turn, you may play that card without paying its mana cost.
Storm (When you cast this spell, copy it for each spell cast before it this turn.)

Worn Powerstone

Worn Powerstone enters tapped.
{T}: Add {C}{C}.

Awoken Horror

When this creature transforms into Awoken Horror, return all non-Horror creatures to their owners' hands.

Thing in the Ice

Defender
Thing in the Ice enters with four ice counters on it.
Whenever you cast an instant or sorcery spell, remove an ice counter from Thing in the Ice. Then if it has no ice counters on it, transform it.

Thing in the Ice // Awoken Horror

The Magic Mirror

This spell costs {1} less to cast for each instant and sorcery card in your graveyard.
You have no maximum hand size.
At the beginning of your upkeep, put a knowledge counter on The Magic Mirror, then draw a card for each knowledge counter on The Magic Mirror.

Mists of Lórien

Replicate {U} (When you cast this spell, copy it for each time you paid its replicate cost. You may choose new targets for the copies.)
Return target nonland permanent and each other nonland permanent with the same mana value as that permanent to their owners' hands.

Gitaxian Probe

({U/P} can be paid with either {U} or 2 life.)
Look at target player's hand.
Draw a card.

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.)

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.

Vedalken Orrery

You may cast spells as though they had flash.

Mystic Sanctuary

({T}: Add {U}.)
Mystic Sanctuary enters tapped unless you control three or more other Islands.
When Mystic Sanctuary enters untapped, you may put target instant or sorcery card from your graveyard on top of your library.

Mirrorpool

Mirrorpool enters tapped.
{T}: Add {C}.
{2}{C}, {T}, Sacrifice Mirrorpool: Copy target instant or sorcery spell you control. You may choose new targets for the copy.
{4}{C}, {T}, Sacrifice Mirrorpool: Create a token that's a copy of target creature you control.

Summary Dismissal

Exile all other spells and counter all abilities.

Murmuring Mystic

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

Brainstorm

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

The Mirari Conjecture

(As this Saga enters and after your draw step, add a lore counter. Sacrifice after III.)
I — Return target instant card from your graveyard to your hand.
II — Return target sorcery card from your graveyard to your hand.
III — Until end of turn, whenever you cast an instant or sorcery spell, copy it. You may choose new targets for the copy.

Expropriate

Council's dilemma — Starting with you, each player votes for time or money. For each time vote, take an extra turn after this one. For each money vote, choose a permanent owned by the voter and gain control of it. Exile Expropriate.

Runechanter's Pike

Equipped creature has first strike and gets +X/+0, where X is the number of instant and sorcery cards in your graveyard.
Equip {2}

Sphinx of the Final Word

This spell can't be countered.
Flying, hexproof
Instant and sorcery spells you control can't be countered.

Mystical Tutor

Search your library for an instant or sorcery card, reveal it, then shuffle and put that card on top.

Mulldrifter

Flying
When Mulldrifter enters, draw two cards.
Evoke {2}{U} (You may cast this spell for its evoke cost. If you do, it's sacrificed when it enters.)

Narset, Parter of Veils

Each opponent can't draw more than one card each turn.
−2: Look at the top four cards of your library. You may reveal a noncreature, nonland card from among them and put it into your hand. Put the rest on the bottom of your library in a random order.

Serum Visions

Supplant Form

Return target creature to its owner's hand. You create a token that's a copy of that creature.

Desertion

Counter target spell. If an artifact or creature spell is countered this way, put that card onto the battlefield under your control instead of into its owner's graveyard.

Capsize

Buyback {3} (You may pay an additional {3} as you cast this spell. If you do, put this card into your hand as it resolves.)
Return target permanent to its owner's hand.