Consider

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

Disruptive Pitmage

{T}: Counter target spell unless its controller pays {1}.
Morph {U} (You may cast this card face down as a 2/2 creature for {3}. Turn it face up any time for its morph cost.)

Sly Instigator

{U}, {T}: Until your next turn, target creature an opponent controls can't be blocked. Goad that creature. (Until your next turn, that creature attacks each combat if able and attacks a player other than you if able.)

Stern Scolding

Counter target creature spell with power or toughness 2 or less.

Midnight Clock

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

Hurl into History

Counter target artifact or creature spell. Discover X, where X is that spell's mana value. (Exile cards from the top of your library until you exile a nonland card with that mana value or less. Cast it without paying its mana cost or put it into your hand. Put the rest on the bottom in a random order.)

Pull from Tomorrow

Saruman's Trickery

Counter target spell.
Amass Orcs 1. (Put a +1/+1 counter on an Army you control. It's also an Orc. If you don't control an Army, create a 0/0 black Orc Army creature token first.)

Island

You Come to a River

Choose one —
• Fight the Current — Return target nonland permanent to its owner's hand.
• Find a Crossing — Target creature gets +1/+0 until end of turn and can't be blocked this turn.

Mnemonic Wall

Defender
When Mnemonic Wall enters the battlefield, you may return target instant or sorcery card from your graveyard to your hand.

Crystal Shard

{3}, {T} or {U}, {T}: Return target creature to its owner's hand unless its controller pays {1}.

Sage's Row Denizen

Whenever another blue creature enters the battlefield under your control, target player mills two cards.

Aether Gale

Return six target nonland permanents to their owners' hands.

Circular Logic

Counter target spell unless its controller pays {1} for each card in your graveyard.
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.)

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.

Talrand, Sky Summoner

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

Sage Owl

Flying
When Sage Owl enters the battlefield, look at the top four cards of your library, then put them back in any order.

Hydromorph Guardian

{U}, Sacrifice Hydromorph Guardian: Counter target spell that targets a creature you control.

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."

Information Dealer

{T}: Look at the top X cards of your library, where X is the number of Wizards on the battlefield, then put them back in any order.

Silver Myr

Turn Aside

Counter target spell that targets a permanent you control.

Parallel Thoughts

When Parallel Thoughts enters the battlefield, search your library for seven cards, exile them in a face-down pile, and shuffle that pile. Then shuffle your library.
If you would draw a card, you may instead put the top card of the pile you exiled into your hand.

Treason of Isengard

Put up to one target instant or sorcery card from your graveyard on top of your library.
Amass Orcs 2. (To amass Orcs 2, put two +1/+1 counters on an Army you control. It's also an Orc. If you don't control an Army, create a 0/0 black Orc Army creature token first.)

Compulsive Research

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

Negate

Condescend

Counter target spell unless its controller pays {X}. Scry 2. (Look at the top two cards of your library, then put any number of them on the bottom of your library and the rest on top in any order.)

The Bath Song

(As this Saga enters and after your draw step, add a lore counter. Sacrifice after III.)
I, II — Draw two cards, then discard a card.
III — Shuffle any number of target cards from your graveyard into your library. Add {U}{U}.

Diluvian Primordial

Flying
When Diluvian Primordial enters the battlefield, for each opponent, you may cast up to one target instant or sorcery card from that player's graveyard without paying its mana cost. If a spell cast this way would be put into a graveyard, exile it instead.

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.

Minor Misstep

Counter target spell with mana value 1 or less.

Override

Counter target spell unless its controller pays {1} for each artifact you control.

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.

Dispersal Shield

Counter target spell if its mana value is less than or equal to the highest mana value among permanents you control.

Scatter Arc

Counter target noncreature spell.
Draw a card.

Glorious Gale

Counter target creature spell. If it was a legendary spell, the Ring tempts you.

Chart a Course

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

Chancellor of the Spires

You may reveal this card from your opening hand. If you do, at the beginning of the first upkeep, each opponent mills seven cards.
Flying
When Chancellor of the Spires enters the battlefield, you may cast target instant or sorcery card from an opponent's graveyard without paying its mana cost.

Annul

Counter target artifact or enchantment spell.

Curse of the Swine

Exile X target creatures. For each creature exiled this way, its controller creates a 2/2 green Boar creature token.

Alter Reality

Change the text of target spell or permanent by replacing all instances of one color word with another. (This effect lasts indefinitely.)
Flashback {1}{U} (You may cast this card from your graveyard for its flashback cost. Then exile it.)

Redirect

You may choose new targets for target spell.

Echoing Truth

Return target nonland permanent and all other permanents with the same name as that permanent to their owners' hands.

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.

Syncopate

Counter target spell unless its controller pays {X}. If that spell is countered this way, exile it instead of putting it into its owner's graveyard.

Azami, Lady of Scrolls

Tap an untapped Wizard you control: Draw a card.

Disarm

Unattach all Equipment from target creature.

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.

Crookclaw Elder

Flying
Tap two untapped Birds you control: Draw a card.
Tap two untapped Wizards you control: Target creature gains flying until end of turn.

Ichor Synthesizer

Whenever you cast a noncreature spell, put an oil counter on Ichor Synthesizer.
As long as Ichor Synthesizer has four or more oil counters on it, it gets +2/+0 and can't be blocked.

Out of Air

This spell costs {2} less to cast if it targets a creature spell.
Counter target spell.

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.)

Ancestral Reminiscence

Rush of Knowledge

Draw cards equal to the highest mana value among permanents you control.

Psychic Barrier

Counter target creature spell. Its controller loses 1 life.

Callous Oppressor

You may choose not to untap Callous Oppressor during your untap step.
As Callous Oppressor enters the battlefield, an opponent chooses a creature type.
{T}: Gain control of target creature that isn't of the chosen type for as long as Callous Oppressor remains tapped.

Thought Courier

Early Frost

Liquify

Counter target spell with mana value 3 or less. If that spell is countered this way, exile it instead of putting it into its owner's graveyard.

Split the Party

Choose target player. Return half the creatures they control to their owner's hand, rounded up.

Boon of the Wish-Giver

Draw four cards.
Cycling {1} ({1}, Discard this card: Draw a card.)

Divert

Change the target of target spell with a single target unless that spell's controller pays {2}.

Switcheroo

Exchange control of two target creatures.

Oracle of Tragedy

When Oracle of Tragedy enters the battlefield or dies, choose one —
• Draw a card, then discard a card.
• Shuffle up to four target cards with mana value 3 or greater from your graveyard into your library.

Stasis Field

Enchant creature
Enchanted creature has base power and toughness 0/2, has defender, and loses all other abilities.

Sleight of Hand

Look at the top two cards of your library. Put one of them into your hand and the other on the bottom of your library.

Spire Golem

Affinity for Islands (This spell costs {1} less to cast for each Island you control.)
Flying

Jace's Sanctum

Instant and sorcery spells you cast cost {1} less to cast.
Whenever you cast an instant or sorcery spell, scry 1. (Look at the top card of your library. You may put that card on the bottom of your library.)

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

Counter target spell. That spell's controller may draw a card.

Voyage's End

Return target creature to its owner's hand. Scry 1. (Look at the top card of your library. You may put that card on the bottom of your library.)