Counterspell

Mask of the Schemer

Whenever equipped creature deals combat damage to a player, it connives X, where X is the amount of damage it dealt to that player. (Draw X cards, then discard X cards. Put a +1/+1 counter on that creature for each nonland card discarded this way.)
Equip {2}

Everflowing Chalice

Multikicker {2} (You may pay an additional {2} any number of times as you cast this spell.)
This artifact enters with a charge counter on it for each time it was kicked.
{T}: Add {C} for each charge counter on this artifact.

Folio of Fancies

Players have no maximum hand size.
{X}{X}, {T}: Each player draws X cards.
{2}{U}, {T}: Each opponent mills cards equal to the number of cards in their hand.

Rapid Hybridization

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

Pongify

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

Mask of Avacyn

Equipped creature gets +1/+2 and has hexproof. (It can't be the target of spells or abilities your opponents control.)
Equip {3}

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.

Rhystic Study

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

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.)

Teferi's Ageless Insight

If you would draw a card except the first one you draw in each of your draw steps, draw two cards instead.

War Room

{T}: Add {C}.
{3}, {T}, Pay life equal to the number of colors in your commanders' color identity: Draw a card.

Blackblade Reforged

Equipped creature gets +1/+1 for each land you control.
Equip legendary creature {3}
Equip {7}

Dig Through Time

Delve (Each card you exile from your graveyard while casting this spell pays for {1}.)
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 any order.

Empyrial Plate

Equipped creature gets +1/+1 for each card in your hand.
Equip {2}

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.")

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.

Wizard Class

(Gain the next level as a sorcery to add its ability.)
You have no maximum hand size.
{2}{U}: Level 2
When this Class becomes level 2, draw two cards.
{4}{U}: Level 3
Whenever you draw a card, put a +1/+1 counter on target creature you control.

Nezahal, Primal Tide

This spell can't be countered.
You have no maximum hand size.
Whenever an opponent casts a noncreature spell, draw a card.
Discard three cards: Exile Nezahal. Return it to the battlefield tapped under its owner's control at the beginning of the next end step.

Windfall

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

Kefnet the Mindful

Flying, indestructible
Kefnet can't attack or block unless you have seven or more cards in hand.
{3}{U}: Draw a card, then you may return a land you control to its owner's hand.

Imprisoned in the Moon

Enchant creature, land, or planeswalker
Enchanted permanent is a colorless land with "{T}: Add {C}" and loses all other card types and abilities.

Midnight Clock

{T}: Add {U}.
{2}{U}: Put an hour counter on this artifact.
At the beginning of each upkeep, put an hour counter on this artifact.
When the twelfth hour counter is put on this artifact, shuffle your hand and graveyard into your library, then draw seven cards. Exile this artifact.

Mystic Sanctuary

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

Desert of the Mindful

This land enters tapped.
{T}: Add {U}.
Cycling {1}{U} ({1}{U}, Discard this card: Draw a card.)

Rogue's Passage

{T}: Add {C}.
{4}, {T}: Target creature can't be blocked this turn.

Sword of Vengeance

Equipped creature gets +2/+0 and has first strike, vigilance, trample, and haste.
Equip {3}

Lonely Sandbar

This land enters tapped.
{T}: Add {U}.
Cycling {U} ({U}, Discard this card: Draw a card.)

Whir of Invention

Improvise (Your artifacts can help cast this spell. Each artifact you tap after you're done activating mana abilities pays for {1}.)
Search your library for an artifact card with mana value X or less, put it onto the battlefield, then shuffle.

Frantic Search

Draw two cards, then discard two cards. Untap up to three lands.

Thirst for Discovery

Draw three cards. Then discard two cards unless you discard a basic land card.

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.

Venser's Journal

You have no maximum hand size.
At the beginning of your upkeep, you gain 1 life for each card in your hand.

Flow of Knowledge

Draw a card for each Island you control, then discard two cards.

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.

The Reality Chip

You may look at the top card of your library any time.
As long as The Reality Chip is attached to a creature, you may play lands and cast spells from the top of your library.
Reconfigure {2}{U} ({2}{U}: Attach to target creature you control; or unattach from a creature. Reconfigure only as a sorcery. While attached, this isn't a creature.)

Fireshrieker

Equipped creature has double strike. (It deals both first-strike and regular combat damage.)
Equip {2} ({2}: Attach to target creature you control. Equip only as a sorcery.)

Sol Ring

Terrain Generator

{T}: Add {C}.
{2}, {T}: You may put a basic land card from your hand onto the battlefield tapped.

Blue Sun's Zenith

Target player draws X cards. Shuffle Blue Sun's Zenith into its owner's library.

Mind Stone

{T}: Add {C}.
{1}, {T}, Sacrifice this artifact: Draw a card.

Mystic Remora

Cumulative upkeep {1} (At the beginning of your upkeep, put an age counter on this permanent, then sacrifice it unless you pay its upkeep cost for each age counter on it.)
Whenever an opponent casts a noncreature spell, you may draw a card unless that player pays {4}.

Curator's Ward

Enchant permanent
Enchanted permanent has hexproof.
When enchanted permanent leaves the battlefield, if it was historic, draw two cards. (Artifacts, legendaries, and Sagas are historic.)

Nevinyrral's Disk

This artifact enters tapped.
{1}, {T}: Destroy all artifacts, creatures, and enchantments.

Treasure Cruise

Delve (Each card you exile from your graveyard while casting this spell pays for {1}.)
Draw three cards.

Wayfarer's Bauble

{2}, {T}, Sacrifice this artifact: Search your library for a basic land card, put that card onto the battlefield tapped, then shuffle.

Reliquary Tower

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

Chasm Skulker

Whenever you draw a card, put a +1/+1 counter on this creature.
When this creature dies, create X 1/1 blue Squid creature tokens with islandwalk, where X is the number of +1/+1 counters on this creature. (They can't be blocked as long as defending player controls an Island.)

Tribute Mage

When this creature enters, you may search your library for an artifact card with mana value 2, reveal that card, put it into your hand, then shuffle.

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.

Wiretapping

Hideaway 5 (When this enchantment enters, look at the top five cards of your library, exile one face down, then put the rest on the bottom in a random order.)
Whenever you draw your first card during each of your draw steps, draw a card. Then if you have nine or more cards in hand, you may play the exiled card without paying its mana cost.

Narset's Reversal

Copy target instant or sorcery spell, then return it to its owner's hand. You may choose new targets for the copy.

Engulf the Shore

Return to their owners' hands all creatures with toughness less than or equal to the number of Islands you control.

Island

Dreamscape Artist

{2}{U}, {T}, Discard a card, Sacrifice a land: Search your library for up to two basic land cards, put them onto the battlefield, then shuffle.

Pull from Tomorrow

High Tide

Until end of turn, whenever a player taps an Island for mana, that player adds an additional {U}.

Training Grounds

Activated abilities of creatures you control cost {2} less to activate. This effect can't reduce the mana in that cost to less than one mana.

Castle Vantress

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

Combat Research

Enchant creature
Enchanted creature has "Whenever this creature deals combat damage to a player, draw a card."
As long as enchanted creature is legendary, it gets +1/+1 and has ward {1}. (Whenever enchanted creature becomes the target of a spell or ability an opponent controls, counter it unless that player pays {1}.)

Toothy, Imaginary Friend

Partner with Pir, Imaginative Rascal (When this creature enters, target player may put Pir into their hand from their library, then shuffle.)
Whenever you draw a card, put a +1/+1 counter on Toothy.
When Toothy leaves the battlefield, draw a card for each +1/+1 counter on it.

Sea Gate, Reborn

As this land enters, you may pay 3 life. If you don't, it enters tapped.
{T}: Add {U}.

Sea Gate Restoration

Draw cards equal to the number of cards in your hand plus one. You have no maximum hand size for the rest of the game.

Sea Gate Restoration // Sea Gate, Reborn

Inquisitor's Flail

If equipped creature would deal combat damage, it deals double that damage instead.
If another creature would deal combat damage to equipped creature, it deals double that damage to equipped creature instead.
Equip {2}

Body of Knowledge

Body of Knowledge's power and toughness are each equal to the number of cards in your hand.
You have no maximum hand size.
Whenever this creature is dealt damage, draw that many cards.

Arcane Signet

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

Fabricate

Search your library for an artifact card, reveal it, put it into your hand, then shuffle.

Fellwar Stone

{T}: Add one mana of any color that a land an opponent controls could produce.

Deep Analysis

Target player draws two cards.
Flashback—{1}{U}, Pay 3 life. (You may cast this card from your graveyard for its flashback cost. Then exile it.)

Loyal Drake

Flying
Lieutenant — At the beginning of combat on your turn, if you control your commander, draw a card.

Commander's Plate

Equipped creature gets +3/+3 and has protection from each color that's not in your commander's color identity.
Equip commander {3}
Equip {5}

Swiftfoot Boots

Equipped creature has hexproof and haste. (It can't be the target of spells or abilities your opponents control. It can attack and {T} no matter when it came under your control.)
Equip {1} ({1}: Attach to target creature you control. Equip only as a sorcery.)

Aetherize

Return all attacking creatures to their owner's hand.

Worldslayer

Whenever equipped creature deals combat damage to a player, destroy all permanents other than this Equipment.
Equip {5} ({5}: Attach to target creature you control. Equip only as a sorcery.)

Psychosis Crawler

Psychosis Crawler's power and toughness are each equal to the number of cards in your hand.
Whenever you draw a card, each opponent loses 1 life.

Stormtide Leviathan

Islandwalk (This creature can't be blocked as long as defending player controls an Island.)
All lands are Islands in addition to their other types.
Creatures without flying or islandwalk can't attack.

Mask of Memory

Whenever equipped creature deals combat damage to a player, you may draw two cards. If you do, discard a card.
Equip {1} ({1}: Attach to target creature you control. Equip only as a sorcery.)

Witness Protection

Enchant creature
Enchanted creature loses all abilities and is a green and white Citizen creature with base power and toughness 1/1 named Legitimate Businessperson. (It loses all other colors, card types, creature types, and names.)

Chart a Course

Draw two cards. Then discard a card unless you attacked this turn.

Brainstorm

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

Triskaidekaphile

You have no maximum hand size.
At the beginning of your upkeep, if you have exactly thirteen cards in your hand, you win the game.
{3}{U}: Draw a card.

O-Naginata

This Equipment can be attached only to a creature with power 3 or greater.
Equipped creature gets +3/+0 and has trample.
Equip {2} ({2}: Attach to target creature you control. Equip only as a sorcery.)