Consider

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

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.

Niblis of Frost

Flying
Prowess (Whenever you cast a noncreature spell, this creature gets +1/+1 until end of turn.)
Whenever you cast an instant or sorcery spell, tap target creature an opponent controls. That creature doesn't untap during its controller's next untap step.

Sky Diamond

This artifact enters tapped.
{T}: Add {U}.

Sphinx of the Second Sun

Flying
At the beginning of each of your postcombat main phases, there is an additional beginning phase after this phase. (The beginning phase includes the untap, upkeep, and draw steps.)

Twisted Image

Switch target creature's power and toughness until end of turn.
Draw a card.

Long River's Pull

Gift a card (You may promise an opponent a gift as you cast this spell. If you do, they draw a card before its other effects.)
Counter target creature spell. If the gift was promised, instead counter target spell.

Wizard's Retort

This spell costs {1} less to cast if you control a Wizard.
Counter target spell.

Planar Atlas

Planar Atlas enters tapped.
When Planar Atlas enters, you may look at the top four cards of your library. If you do, reveal up to one land card from among them, then put that card on top of your library and the rest on the bottom in a random order.
{T}: Add {C}.

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.)

Riptide Laboratory

{T}: Add {C}.
{1}{U}, {T}: Return target Wizard you control to its owner's hand.

Curse of the Swine

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

Treasure Cruise

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

Island

Fleeting Distraction

Target creature gets -1/-0 until end of turn.
Draw a card.

Dispel

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.)

Aetherspouts

For each attacking creature, its owner puts it on their choice of the top or bottom of their library.

Ravenform

Exile target artifact or creature. Its controller creates a 1/1 blue Bird creature token with flying.
Foretell {U} (During your turn, you may pay {2} and exile this card from your hand face down. Cast it on a later turn for its foretell cost.)

Tune the Narrative

Draw a card. You get {E}{E} (two energy counters).

Wavebreak Hippocamp

Whenever you cast your first spell during each opponent's turn, draw a card.

Change the Equation

Choose one —
• Counter target spell with mana value 2 or less.
• Counter target red or green spell with mana value 6 or less.

Chilling Trap

Target creature gets -4/-0 until end of turn. If you control a Wizard, draw a card.

Flow of Knowledge

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

Mind Stone

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

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.

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.")

Curiosity Crafter

Flying
You have no maximum hand size.
Whenever a creature token you control deals combat damage to a player, draw a card.

Staff of the Mind Magus

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

Saw It Coming

Counter target spell.
Foretell {1}{U} (During your turn, you may pay {2} and exile this card from your hand face down. Cast it on a later turn for its foretell cost.)

Take the Fall

Target creature gets -1/-0 until end of turn. It gets -4/-0 until end of turn instead if you control an outlaw. (Assassins, Mercenaries, Pirates, Rogues, and Warlocks are outlaws.)
Draw a card.

Peek

Look at target player's hand.
Draw a card.

Shadow of the Second Sun

Enchant player
At the beginning of each of enchanted player's postcombat main phases, there is an additional beginning phase after this phase. (The end step happens after the added untap, upkeep, and draw steps.)

Oona's Grace

Target player draws a card.
Retrace (You may cast this card from your graveyard by discarding a land card in addition to paying its other costs.)

Kraken's Eye

Whenever a player casts a blue spell, you may gain 1 life.

Filter Out

Return all noncreature, nonland permanents to their owners' hands.

Stream of Unconsciousness

Solar Transformer

This artifact enters tapped.
When this artifact enters, you get {E}{E}{E} (three energy counters).
{T}: Add {C}.
{T}, Pay {E}: Add one mana of any color.

Coastal Piracy

Whenever a creature you control deals combat damage to an opponent, you may draw a card.

Forbid

Buyback—Discard two cards. (You may discard two cards in addition to any other costs as you cast this spell. If you do, put this card into your hand as it resolves.)
Counter target spell.

Deepfathom Skulker

Devoid (This card has no color.)
Whenever a creature you control deals combat damage to a player, you may draw a card.
{3}{C}: Target creature can't be blocked this turn. ({C} represents colorless mana.)

Archmage of Runes

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

Neutralize

Counter target spell.
Cycling {2} ({2}, Discard this card: Draw a card.)

Arcane Signet

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

Unwind

Counter target noncreature spell. Untap up to three lands.

Spell Syphon

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

Thought Scour

Target player mills two cards.
Draw a card.

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.

Reach Through Mists

Counterspell

Talrand, Sky Summoner

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

Archmage Emeritus

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

Final Iteration

Flying
Wizards you control get +2/+1 and have flying.
Whenever you cast an instant or sorcery spell, create a 1/1 blue Human Wizard creature token.

Docent of Perfection

Flying
Whenever you cast an instant or sorcery spell, create a 1/1 blue Human Wizard creature token. Then if you control three or more Wizards, transform this creature.

Docent of Perfection // Final Iteration

Frantic Search

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

Reconnaissance Mission

Whenever a creature you control deals combat damage to a player, you may draw a card.
Cycling {2} ({2}, Discard this card: Draw a card.)

Spell Satchel

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

Mocking Sprite

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

The Phasing of Zhalfir

Read ahead (Choose a chapter and start with that many lore counters. Add one after your draw step. Skipped chapters don't trigger. Sacrifice after III.)
I, II — Another target nonland permanent phases out. It can't phase in for as long as you control this Saga.
III — Destroy all creatures. For each creature destroyed this way, its controller creates a 2/2 black Phyrexian creature token.

Rapid Hybridization

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

Lunar Mystic

Whenever you cast an instant spell, you may pay {1}. If you do, draw a card.

Aetherize

Return all attacking creatures to their owner's hand.

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.

Whispers of the Muse

Buyback {5} (You may pay an additional {5} as you cast this spell. If you do, put this card into your hand as it resolves.)
Draw a card.

Star Compass

This artifact enters tapped.
{T}: Add one mana of any color that a basic land you control could produce.

Glimpse of Freedom

Draw a card.
Escape—{2}{U}, Exile five other cards from your graveyard. (You may cast this card from your graveyard for its escape cost.)

Negate

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

Echoing Truth

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

Confound

Counter target spell that targets a creature.
Draw a card.

Disdainful Stroke

Counter target spell with mana value 4 or greater.

Wash Out

Return all permanents of the color of your choice to their owners' hands.

Quicken

The next sorcery spell you cast this turn can be cast as though it had flash. (It can be cast any time you could cast an instant.)
Draw a card.

Flow of Ideas

Rewind

Counter target spell. Untap up to four lands.

Geyser Drake

Flying
During turns other than yours, spells you cast cost {1} less to cast.