Thought Scour

Target player mills two cards.
Draw a card.

Stenn, Paranoid Partisan

As Stenn, Paranoid Partisan enters, choose a card type other than creature or land.
Spells you cast of the chosen type cost {1} less to cast.
{1}{W}{U}: Exile Stenn. Return it to the battlefield under its owner's control at the beginning of the next end step.

Enter the Infinite

Draw cards equal to the number of cards in your library, then put a card from your hand on top of your library. You have no maximum hand size until your next turn.

Fabricate

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

Mitotic Manipulation

Look at the top seven cards of your library. You may put one of those cards onto the battlefield if it has the same name as a permanent. Put the rest on the bottom of your library in any order.

Arcane Signet

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

Ballad of the Black Flag

(As this Saga enters and after your draw step, add a lore counter. Sacrifice after IV.)
I, II, III — Mill three cards. You may put a historic card from among them into your hand. (Artifacts, legendaries, and Sagas are historic.)
IV — Historic spells you cast this turn cost {2} less to cast.

Jace's Sanctum

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

Laboratory Maniac

If you would draw a card while your library has no cards in it, you win the game instead.

Kefnet's Monument

Blue creature spells you cast cost {1} less to cast.
Whenever you cast a creature spell, target creature an opponent controls doesn't untap during its controller's next untap step.

Case of the Ransacked Lab

Instant and sorcery spells you cast cost {1} less to cast.
To solve — You've cast four or more instant and sorcery spells this turn. (If unsolved, solve at the beginning of your end step.)
Solved — Whenever you cast an instant or sorcery spell, draw a card.

Psychic Corrosion

Whenever you draw a card, each opponent mills two cards.

Archmage Emeritus

Magecraft — Whenever you cast or copy an instant or sorcery spell, draw a card.

Retraced Image

Reveal a card in your hand, then put that card onto the battlefield if it has the same name as a permanent.

Sol Ring

Propaganda

Creatures can't attack you unless their controller pays {2} for each creature they control that's attacking you.

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.)

Mocking Sprite

Flying
Instant and sorcery spells you cast cost {1} less to cast.

Sapphire Medallion

Blue spells you cast cost {1} less to cast.

Azorius Chancery

Azorius Chancery enters tapped.
When Azorius Chancery enters, return a land you control to its owner's hand.
{T}: Add {W}{U}.

Hive Mind

Whenever a player casts an instant or sorcery spell, each other player copies that spell. Each of those players may choose new targets for their copy.

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.

Grand Arbiter Augustin IV

White spells you cast cost {1} less to cast.
Blue spells you cast cost {1} less to cast.
Spells your opponents cast cost {1} more to cast.

Mindsplice Apparatus

Flash
At the beginning of your upkeep, put an oil counter on Mindsplice Apparatus.
Instant and sorcery spells you cast cost {1} less to cast for each oil counter on Mindsplice Apparatus.

Frantic Search

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

Thassa's Oracle

When Thassa's Oracle enters, look at the top X cards of your library, where X is your devotion to blue. Put up to one of them on top of your library and the rest on the bottom of your library in a random order. If X is greater than or equal to the number of cards in your library, you win the game. (Each {U} in the mana costs of permanents you control counts toward your devotion to blue.)

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.

Dictate of Kruphix

Flash (You may cast this spell any time you could cast an instant.)
At the beginning of each player's draw step, that player draws an additional card.

Windfall

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

Prairie Stream

({T}: Add {W} or {U}.)
Prairie Stream enters tapped unless you control two or more basic lands.

Cloud Key

As Cloud Key enters, choose artifact, creature, enchantment, instant, or sorcery.
Spells you cast of the chosen type cost {1} less to cast.

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.)

Urza's Saga

(As this Saga enters and after your draw step, add a lore counter. Sacrifice after III.)
I — Urza's Saga gains "{T}: Add {C}."
II — Urza's Saga gains "{2}, {T}: Create a 0/0 colorless Construct artifact creature token with 'This creature gets +1/+1 for each artifact you control.'"
III — Search your library for an artifact card with mana cost {0} or {1}, put it onto the battlefield, then shuffle.

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.

Deserted Beach

Deserted Beach enters tapped unless you control two or more other lands.
{T}: Add {W} or {U}.

Mystical Tutor

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

Mana Matrix

Instant and enchantment spells you cast cost {2} less to cast.

Nimbus Maze

{T}: Add {C}.
{T}: Add {W}. Activate only if you control an Island.
{T}: Add {U}. Activate only if you control a Plains.

Snow-Covered Plains

Anvil of Bogardan

Players have no maximum hand size.
At the beginning of each player's draw step, that player draws an additional card, then discards 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}.

Foundry Inspector

Artifact spells you cast cost {1} less to cast.

Consider

Surveil 1. (Look at the top card of your library. You may put it into your graveyard.)
Draw a card.

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.

Kami of the Crescent Moon

At the beginning of each player's draw step, that player draws an additional card.

Snow-Covered Island

Nykthos, Shrine to Nyx

{T}: Add {C}.
{2}, {T}: Choose a color. Add an amount of mana of that color equal to your devotion to that color. (Your devotion to a color is the number of mana symbols of that color in the mana costs of permanents you control.)

Ormos, Archive Keeper

Flying
If you would draw a card while your library has no cards in it, instead put five +1/+1 counters on Ormos, Archive Keeper.
{1}{U}{U}, Discard three cards with different names: Draw five cards.

Jhoira's Familiar

Flying
Historic spells you cast cost {1} less to cast. (Artifacts, legendaries, and Sagas are historic.)

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.

Ugin, the Ineffable

Colorless spells you cast cost {2} less to cast.
+1: Exile the top card of your library face down and look at it. Create a 2/2 colorless Spirit creature token. When that token leaves the battlefield, put the exiled card into your hand.
−3: Destroy target permanent that's one or more colors.

Voracious Reader

Prowess (Whenever you cast a noncreature spell, this creature gets +1/+1 until end of turn.)
Instant and sorcery spells you cast cost {1} less to cast.

Curious Homunculus

{T}: Add {C}. Spend this mana only to cast an instant or sorcery spell.
At the beginning of your upkeep, if there are three or more instant and/or sorcery cards in your graveyard, transform Curious Homunculus.

Curious Homunculus // Voracious Reader

High Tide

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

Nyx Lotus

Nyx Lotus enters tapped.
{T}: Choose a color. Add an amount of mana of that color equal to your devotion to that color. (Your devotion to a color is the number of mana symbols of that color in the mana costs of permanents you control.)

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.

Sea of Clouds

Sea of Clouds enters tapped unless you have two or more opponents.
{T}: Add {W} or {U}.

Alandra, Sky Dreamer

Whenever you draw your second card each turn, create a 2/2 blue Drake creature token with flying.
Whenever you draw your fifth card each turn, Alandra, Sky Dreamer and Drakes you control each get +X/+X until end of turn, where X is the number of cards in your hand.

Scry 1. (Look at the top card of your library. You may put that card on the bottom.)
Draw a card.

Howling Mine

At the beginning of each player's draw step, if Howling Mine is untapped, that player draws an additional card.

Thunderclap Drake

Flying
Instant and sorcery spells you cast cost {1} less to cast.
{2}{U}, Sacrifice Thunderclap Drake: When you next cast an instant or sorcery spell this turn, copy it for each time you've cast your commander from the command zone this game. You may choose new targets for the copies.

Glacial Fortress

Glacial Fortress enters tapped unless you control a Plains or an Island.
{T}: Add {W} or {U}.

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.

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.

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.

Long-Forgotten Gohei

Arcane spells you cast cost {1} less to cast.
Spirit creatures you control get +1/+1.

Ponder

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

Command Tower

Etherium Sculptor

Esper Sentinel

Whenever an opponent casts their first noncreature spell each turn, draw a card unless that player pays {X}, where X is Esper Sentinel's power.