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.

Hapless Researcher

Sacrifice Hapless Researcher: Draw a card, then discard a card.

Chilling Chronicle

{1}, {T}: Tap target nonland permanent. Transform Chilling Chronicle.

Mysterious Tome

{2}, {T}: Draw a card. Transform Mysterious Tome.

Mysterious Tome // Chilling Chronicle

Firemind Vessel

Firemind Vessel enters tapped.
{T}: Add two mana of different colors.

Mangara's Tome

When Mangara's Tome enters, search your library for five cards, exile them in a face-down pile, and shuffle that pile. Then shuffle your library.
{2}: The next time you would draw a card this turn, instead put the top card of the exiled pile into its owner's hand.

Resculpt

Exile target artifact or creature. Its controller creates a 4/4 blue and red Elemental creature token.

Perilous Research

Draw two cards, then sacrifice a permanent.

Increasing Confusion

Target player mills X cards. If this spell was cast from a graveyard, that player mills twice that many cards instead.
Flashback {X}{U} (You may cast this card from your graveyard for its flashback cost. Then exile it.)

Step Through

Return two target creatures to their owners' hands.
Wizardcycling {2} ({2}, Discard this card: Search your library for a Wizard card, reveal it, put it into your hand, then shuffle.)

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.

Plagiarize

Until end of turn, if target player would draw a card, instead that player skips that draw and you draw a card.

Willbreaker

Whenever a creature an opponent controls becomes the target of a spell or ability you control, gain control of that creature for as long as you control Willbreaker.

Soldevi Sage

{T}, Sacrifice two lands: Draw three cards, then discard one of them.

Unstable Obelisk

{T}: Add {C}.
{7}, {T}, Sacrifice Unstable Obelisk: Destroy target permanent.

Jayemdae Tome

Learn from the Past

Target player shuffles their graveyard into their library.
Draw a card.

Gadwick, the Wizened

When Gadwick, the Wizened enters, draw X cards.
Whenever you cast a blue spell, tap target nonland permanent an opponent controls.

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].

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.)

Living Lectern

{1}, Sacrifice Living Lectern: Draw a card. Create a Sorcerer Role token attached to up to one other target creature you control. Activate only as a sorcery. (If you control another Role on it, put that one into the graveyard. Enchanted creature gets +1/+1 and has "Whenever this creature attacks, scry 1.")

Careful Study

Artificer's Assistant

Flying
Whenever you cast a historic spell, scry 1. (Artifacts, legendaries, and Sagas are historic. To scry 1, look at the top card of your library, then you may put that card on the bottom.)

Curse of the Bloody Tome

Enchant player
At the beginning of enchanted player's upkeep, that player mills two cards.

Commander's Sphere

{T}: Add one mana of any color in your commander's color identity.
Sacrifice Commander's Sphere: Draw a card.

You Find the Villains' Lair

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

Overwhelmed Apprentice

When Overwhelmed Apprentice enters, each opponent mills two cards. Then you 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.)

Reckless Scholar

{T}: Target player draws a card, then discards a card.

Academy Loremaster

At the beginning of each player's draw step, that player may draw an additional card. If they do, spells they cast this turn cost {2} more to cast.

Ideas Unbound

Draw three cards. Discard three cards at the beginning of the next end step.

Flow of Knowledge

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

Sage's Row Denizen

Whenever another blue creature you control enters, target player mills two cards.

Scroll Thief

Whenever Scroll Thief deals combat damage to a player, draw a card.

Thran Tome

{5}, {T}: Reveal the top three cards of your library. Target opponent chooses one of those cards. Put that card into your graveyard, then draw two cards.

Otherworld Atlas

{T}: Put a charge counter on Otherworld Atlas.
{T}: Each player draws a card for each charge counter on Otherworld Atlas.

Library of Lat-Nam

An opponent chooses one —
• You draw three cards at the beginning of the next turn's upkeep.
• You search your library for a card, put that card into your hand, then shuffle.

Kyren Archive

At the beginning of your upkeep, you may exile the top card of your library face down.
{5}, Discard your hand, Sacrifice Kyren Archive: Put all cards exiled with Kyren Archive into their owner's hand.

Gadwick's First Duel

(As this Saga enters and after your draw step, add a lore counter. Sacrifice after III.)
I — Create a Cursed Role token attached to up to one target creature. (If you control another Role on it, put that one into the graveyard. Enchanted creature is 1/1.)
II — Scry 2.
III — When you next cast an instant or sorcery spell with mana value 3 or less this turn, copy that spell. You may choose new targets for the copy.

Tome Anima

Tome Anima can't be blocked as long as you've drawn two or more cards this turn.

Tenacious Tomeseeker

Bargain (You may sacrifice an artifact, enchantment, or token as you cast this spell.)
When Tenacious Tomeseeker enters, if it was bargained, return target instant or sorcery card from your graveyard to your hand.

Archaeomancer

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

Mystic Redaction

At the beginning of your upkeep, scry 1.
Whenever you discard a card, each opponent mills two cards. (They put the top two cards of their library into their graveyard.)

Disdainful Stroke

Counter target spell with mana value 4 or greater.

Mana Geode

When Mana Geode enters, scry 1.
{T}: Add one mana of any color.

Teferi's Protege

{1}{U}, {T}: Draw a card, then discard a card.

Cold Case Cracker

Flying
When Cold Case Cracker dies, investigate. (Create a Clue token. It's an artifact with "{2}, Sacrifice this artifact: Draw a card.")

Obsessive Search

Draw a card.
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.)

Faerie Vandal

Flash (You may cast this spell any time you could cast an instant.)
Flying
Whenever you draw your second card each turn, put a +1/+1 counter on Faerie Vandal.

Oath of Scholars

At the beginning of each player's upkeep, that player chooses target player who has more cards in hand than they do and is their opponent. The first player may discard their hand and draw three cards.

Treasure Cruise

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

Archivist

Mental Discipline

Otherworldly Gaze

Surveil 3. (Look at the top three cards of your library, then put any number of them into your graveyard and the rest on top of your library in any order.)
Flashback {1}{U} (You may cast this card from your graveyard for its flashback cost. Then exile it.)

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.

Dreamstone Hedron

{T}: Add {C}{C}{C}.
{3}, {T}, Sacrifice Dreamstone Hedron: Draw three cards.

Unsummon

Return target creature to its owner's hand.

Investigator's Journal

Investigator's Journal enters with a number of suspect counters on it equal to the greatest number of creatures a player controls.
{2}, {T}, Remove a suspect counter from Investigator's Journal: Draw a card.
{2}, Sacrifice Investigator's Journal: Draw a card.

Index

Look at the top five cards of your library, then put them back in any order.

Scour the Laboratory

Delirium — This spell costs {2} less to cast if there are four or more card types among cards in your graveyard.
Draw three cards.

Sisay's Ring

Sky Diamond

Impulse

Look at the top four cards of your library. Put one of them into your hand and the rest on the bottom of your library in any order.

Curate

Surveil 2. (Look at the top two cards of your library, then put any number of them into your graveyard and the rest on top of your library in any order.)
Draw a card.

Idle Thoughts

{2}: Draw a card if you have no cards in hand.

Tolarian Scholar

Negate

Lat-Nam Adept

Whenever you draw your second card each turn, put a +1/+1 counter on Lat-Nam Adept.

Field Research

Kicker {2}{U} (You may pay an additional {2}{U} as you cast this spell.)
Draw two cards. If this spell was kicked, draw three cards instead.

Sarpadian Empires, Vol. VII

As Sarpadian Empires, Vol. VII enters, choose white Citizen, blue Camarid, black Thrull, red Goblin, or green Saproling.
{3}, {T}: Create a 1/1 creature token of the chosen color and type.

Laquatus's Creativity

Target player draws cards equal to the number of cards in their hand, then discards that many cards.

Chart a Course

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

Bury in Books

This spell costs {2} less to cast if it targets an attacking creature.
Put target creature into its owner's library second from the top.

Spell Satchel

Magecraft — Whenever you cast or copy an instant or sorcery spell, put a book counter on Spell Satchel.
{T}, Remove a book counter from Spell Satchel: Add {C}.
{3}, {T}, Remove three book counters from Spell Satchel: Draw a card.

Archive Haunt

Flying
Whenever Archive Haunt attacks, draw a card, then discard a card.
If Archive Haunt would be put into a graveyard from anywhere, exile it instead.

Overwhelmed Archivist

When Overwhelmed Archivist enters, draw a card, then discard a card.
Disturb {3}{U} (You may cast this card from your graveyard transformed for its disturb cost.)

Overwhelmed Archivist // Archive Haunt

Prismatic Lens

{T}: Add {C}.
{1}, {T}: Add one mana of any color.

Lat-Nam's Legacy

Shuffle a card from your hand into your library. If you do, draw two cards at the beginning of the next turn's upkeep.

Browse

{2}{U}{U}: Look at the top five cards of your library, put one of them into your hand, and exile the rest.

Tunnel Vision

Choose a card name. Target player reveals cards from the top of their library until a card with that name is revealed. If it is, that player puts the rest of the revealed cards into their graveyard and puts the card with the chosen name on top of their library. Otherwise, the player shuffles.

Arcane Encyclopedia

Letter of Acceptance

{T}: Add one mana of any color.
{2}, {T}, Sacrifice Letter of Acceptance: Draw a card.

Biblioplex Assistant

Flying
When Biblioplex Assistant enters, put up to one target instant or sorcery card from your graveyard on top of your library.

Archive Dragon

Flying
Ward {2} (Whenever this creature becomes the target of a spell or ability an opponent controls, counter it unless that player pays {2}.)
When Archive Dragon enters, scry 2.

Pedantic Learning

Whenever a land card is put into your graveyard from your library, you may pay {1}. If you do, draw a card.

Pore Over the Pages

Draw three cards, untap up to two lands, then discard a card.

Vhal, Candlekeep Researcher

Vigilance
{T}: Add an amount of {C} equal to Vhal, Candlekeep Researcher's toughness. This mana can't be spent to cast spells from your hand.
Choose a Background (You can have a Background as a second commander.)

Evacuation

Return all creatures to their owners' hands.

Divination

Urza's Tome

{3}, {T}: Draw a card. Then discard a card unless you exile a historic card from your graveyard. (Artifacts, legendaries, and Sagas are historic.)

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

Staff of the Mind Magus

Whenever you cast a blue spell or an Island you control enters, you gain 1 life.

Honored Heirloom

{T}: Add one mana of any color.
{2}, {T}: Exile target card from a graveyard.

Flash of Insight

Look at the top X cards of your library. Put one of them into your hand and the rest on the bottom of your library in any order.
Flashback—{1}{U}, Exile X blue cards from your graveyard. (You may cast this card from your graveyard for its flashback cost, then exile it. You can't exile Flash of Insight to pay for its own flashback cost.)

Rewind

Counter target spell. Untap up to four lands.

Unwind

Counter target noncreature spell. Untap up to three lands.

Compulsive Research

Target player draws three cards. Then that player discards two cards unless they discard a land card.

Barrin's Codex

At the beginning of your upkeep, you may put a page counter on Barrin's Codex.
{4}, {T}, Sacrifice Barrin's Codex: Draw X cards, where X is the number of page counters on Barrin's Codex.

Occult Epiphany

Draw X cards, then discard X cards. Create a 1/1 white Spirit creature token with flying for each card type among cards discarded this way.

Network Terminal

{T}: Add one mana of any color.
{1}, {T}, Tap another untapped artifact you control: Draw a card, then discard a card.

Firmament Sage

If it's neither day nor night, it becomes day as Firmament Sage enters.
Whenever day becomes night or night becomes day, draw a card.

Emmessi Tome

{5}, {T}: Draw two cards, then discard a card.

Candlekeep Sage

Commander creatures you own have "When this creature enters or leaves the battlefield, draw a card."

Astral Cornucopia

Astral Cornucopia enters with X charge counters on it.
{T}: Choose a color. Add one mana of that color for each charge counter on Astral Cornucopia.

Hard Cover

Enchant creature
Enchanted creature gets +0/+2 and has "{T}: Draw a card, then discard a card."

Contact Other Plane

Roll a d20.
1—9 | Draw two cards.
10—19 | Scry 2, then draw two cards.
20 | Scry 3, then draw three cards.