Arcane Signet

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

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

Grimoire of the Dead

{1}, {T}, Discard a card: Put a study counter on Grimoire of the Dead.
{T}, Remove three study counters from Grimoire of the Dead and sacrifice it: Put all creature cards from all graveyards onto the battlefield under your control. They're black Zombies in addition to their other colors and types.

Reliquary Tower

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

Sol Ring

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.

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.

Spirebluff Canal

Spirebluff Canal enters the battlefield tapped unless you control two or fewer other lands.
{T}: Add {U} or {R}.

Book of Rass

Cascade Bluffs

{T}: Add {C}.
{U/R}, {T}: Add {U}{U}, {U}{R}, or {R}{R}.

Research Thief

Flash
Flying
Whenever an artifact creature you control deals combat damage to a player, draw a card.

Rise and Shine

Target noncreature artifact you control becomes a 0/0 artifact creature. Put four +1/+1 counters on each artifact that became a creature this way.
Overload {4}{U}{U} (You may cast this spell for its overload cost. If you do, change "target" in its text to "each.")

Firemind's Research

Whenever you cast an instant or sorcery spell, put a charge counter on Firemind's Research.
{1}{U}, Remove two charge counters from Firemind's Research: Draw a card.
{1}{R}, Remove five charge counters from Firemind's Research: It deals 5 damage to any target.

Scholar of the Ages

When Scholar of the Ages enters the battlefield, return up to two target instant and/or sorcery cards from your graveyard to your hand.

Grazilaxx, Illithid Scholar

Whenever a creature you control becomes blocked, you may return it to its owner's hand.
Whenever one or more creatures you control deal combat damage to a player, draw a card.

Library

Library enters the battlefield tapped.
{T}: Add {U} or {R}.
{4}, {T}: Investigate. (Create a Clue token. It's an artifact with "{2}, Sacrifice this artifact: Draw a card.")

Frantic Search

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

Shivan Reef

{T}: Add {C}.
{T}: Add {U} or {R}. Shivan Reef deals 1 damage to you.

Izzet Boilerworks

Izzet Boilerworks enters the battlefield tapped.
When Izzet Boilerworks enters the battlefield, return a land you control to its owner's hand.
{T}: Add {U}{R}.

Mangara's Tome

When Mangara's Tome enters the battlefield, 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.

Book Devourer

Trample
Whenever Book Devourer deals combat damage to a player, you may discard all the cards in your hand. If you do, draw that many cards.

Scalding Tarn

{T}, Pay 1 life, Sacrifice Scalding Tarn: Search your library for an Island or Mountain card, put it onto the battlefield, then shuffle.

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.

Tolarian Scholar

Mystic Retrieval

Return target instant or sorcery card from your graveyard to your hand.
Flashback {2}{R} (You may cast this card from your graveyard for its flashback cost. Then exile it.)

Practical Research

Draw four cards. Then discard two cards unless you discard an instant or sorcery card.

Ingenious Prodigy

Skulk (This creature can't be blocked by creatures with greater power.)
Ingenious Prodigy enters the battlefield with X +1/+1 counters on it.
At the beginning of your upkeep, if Ingenious Prodigy has one or more +1/+1 counters on it, you may remove a +1/+1 counter from it. If you do, draw a card.

Rielle, the Everwise

Rielle, the Everwise gets +1/+0 for each instant and sorcery card in your graveyard.
Whenever you discard one or more cards for the first time each turn, draw that many cards.

Tome Scour

Frostboil Snarl

As Frostboil Snarl enters the battlefield, you may reveal an Island or Mountain card from your hand. If you don't, Frostboil Snarl enters the battlefield tapped.
{T}: Add {U} or {R}.

First Day of Class

Whenever a creature enters the battlefield under your control this turn, put a +1/+1 counter on it and it gains haste until end of turn.
Learn. (You may reveal a Lesson card you own from outside the game and put it into your hand, or discard a card to draw a card.)

Niv-Mizzet, Parun

This spell can't be countered.
Flying
Whenever you draw a card, Niv-Mizzet, Parun deals 1 damage to any target.
Whenever a player casts an instant or sorcery spell, you draw a 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.

Steam Clean

Return target nonland permanent to its owner's hand. (Then exile this card. You may cast the creature later from exile.)

Scalding Viper

Whenever an opponent casts a spell with mana value 3 or less, Scalding Viper deals 1 damage to that player.

Scalding Viper // Steam Clean

Nerd Rage

Enchant creature
When Nerd Rage enters the battlefield, draw two cards.
Enchanted creature has "You have no maximum hand size" and "Whenever this creature attacks, if you have ten or more cards in hand, it gets +10/+10 until end of turn."

Volo, Itinerant Scholar

When Volo enters the battlefield, create Volo's Journal, a legendary colorless artifact token with hexproof and "Whenever you cast a creature spell, note one of its creature types that hasn't been noted for this artifact."
{2}, {T}: Draw a card for each creature type noted for target permanent you control named Volo's Journal.
Choose a Background

Mountain

Izzet Signet

Mordenkainen

+2: Draw two cards, then put a card from your hand on the bottom of your library.
−2: Create a blue Dog Illusion creature token with "This creature's power and toughness are each equal to twice the number of cards in your hand."
−10: Exchange your hand and library, then shuffle. You get an emblem with "You have no maximum hand size."

Spellbook

Tome Raider

Flying
When Tome Raider enters the battlefield, 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.)

Perfected Form

Aberrant Researcher

Flying
At the beginning of your upkeep, mill a card. If an instant or sorcery card was milled this way, transform Aberrant Researcher.

Aberrant Researcher // Perfected Form

Sulfur Falls

Sulfur Falls enters the battlefield tapped unless you control an Island or a Mountain.
{T}: Add {U} or {R}.

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 the battlefield, scry 2.

Archmage Emeritus

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

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.

Reckless Scholar

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

Muddle the Mixture

Counter target instant or sorcery spell.
Transmute {1}{U}{U} ({1}{U}{U}, Discard this card: Search your library for a card with the same mana value as this card, reveal it, put it into your hand, then shuffle. Transmute only as a sorcery.)

Youthful Scholar

When Youthful Scholar dies, draw two cards.

Temple of Epiphany

Temple of Epiphany enters the battlefield tapped.
When Temple of Epiphany enters the battlefield, scry 1.
{T}: Add {U} or {R}.

Unblinking Observer

{T}: Add {U}. Spend this mana only to pay a disturb cost or cast an instant or sorcery spell.

Jalum Tome

{2}, {T}: Draw a card, then discard a card.

Island

Mazemind Tome

{T}, Put a page counter on Mazemind Tome: Scry 1.
{2}, {T}, Put a page counter on Mazemind Tome: Draw a card.
When there are four or more page counters on Mazemind Tome, exile it. If you do, you gain 4 life.

Complete the Circuit

Convoke (Your creatures can help cast this spell. Each creature you tap while casting this spell pays for {1} or one mana of that creature's color.)
You may cast sorcery spells this turn as though they had flash.
When you next cast an instant or sorcery spell this turn, copy that spell twice. You may choose new targets for the copies.

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.)

Curse of the Bloody Tome

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

Compulsive Research

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

Teferi's Protege

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

Revolutionist

When Revolutionist enters the battlefield, return target instant or sorcery card from your graveyard to your hand.
Madness {3}{R} (If you discard this card, discard it into exile. When you do, cast it for its madness cost or put it into your graveyard.)

Library of Alexandria

{T}: Add {C}.
{T}: Draw a card. Activate only if you have exactly seven cards in hand.

Tome Anima

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

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.)

Letter of Acceptance

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

Prismari Campus

Prismari Campus enters the battlefield tapped.
{T}: Add {U} or {R}.
{4}, {T}: Scry 1.

Wizard's Spellbook

{T}: Exile target instant or sorcery card from a graveyard. Roll a d20. Activate only as a sorcery.
1—9 | Copy that card. You may cast the copy.
10—19 | Copy that card. You may cast the copy by paying {1} rather than paying its mana cost.
20 | Copy each card exiled with Wizard's Spellbook. You may cast any number of the copies without paying their mana costs.

Thought Vessel

Sorcerer Class

(Gain the next level as a sorcery to add its ability.)
When Sorcerer Class enters the battlefield, draw two cards, then discard two cards.
{U}{R}: Level 2
Creatures you control have "{T}: Add {U} or {R}. Spend this mana only to cast an instant or sorcery spell or to gain a Class level."
{3}{U}{R}: Level 3
Whenever you cast an instant or sorcery spell, that spell deals damage to each opponent equal to the number of instant and sorcery spells you've cast this turn.

Library Larcenist

Whenever Library Larcenist attacks, draw a card.

Steam Vents

({T}: Add {U} or {R}.)
As Steam Vents enters the battlefield, you may pay 2 life. If you don't, it enters the battlefield tapped.

Suspicious Bookcase

Defender
{3}, {T}: Target creature can't be blocked this turn.

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.")

Command Tower

Izzet Guildgate

Izzet Guildgate enters the battlefield tapped.
{T}: Add {U} or {R}.

Tome Shredder

Haste
{T}, Exile an instant or sorcery card from your graveyard: Put a +1/+1 counter on Tome Shredder.

Ferrous Lake

Rhystic Study

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

Will, Scholar of Frost

Instant and sorcery spells you cast cost {1} less to cast.
+1: Up to one target creature has base power and toughness 0/2 until your next turn.
−3: Draw two cards.
−7: Exile up to five target permanents. For each permanent exiled this way, its controller creates a 4/4 blue and red Elemental creature token.

Rowan, Scholar of Sparks

Instant and sorcery spells you cast cost {1} less to cast.
+1: Rowan, Scholar of Sparks deals 1 damage to each opponent. If you've drawn three or more cards this turn, she deals 3 damage to each opponent instead.
−4: You get an emblem with "Whenever you cast an instant or sorcery spell, you may pay {2}. If you do, copy that spell. You may choose new targets for the copy."