Slip Out the Back

Put a +1/+1 counter on target creature. It phases out. (Treat it and anything attached to it as though they don't exist until its controller's next turn.)

Otawara, Soaring City

{T}: Add {U}.
Channel — {3}{U}, Discard Otawara, Soaring City: Return target artifact, creature, enchantment, or planeswalker to its owner's hand. This ability costs {1} less to activate for each legendary creature you control.

Memory Deluge

Look at the top X cards of your library, where X is the amount of mana spent to cast this spell. Put two of them into your hand and the rest on the bottom of your library in a random order.
Flashback {5}{U}{U} (You may cast this card from your graveyard for its flashback cost. Then exile it.)

Finale of Revelation

Draw X cards. If X is 10 or more, instead shuffle your graveyard into your library, draw X cards, untap up to five lands, and you have no maximum hand size for the rest of the game.
Exile Finale of Revelation.

Enduring Curiosity

Flash
Whenever a creature you control deals combat damage to a player, draw a card.
When Enduring Curiosity dies, if it was a creature, return it to the battlefield under its owner's control. It's an enchantment. (It's not a creature.)

Consider

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

Panharmonicon

If an artifact or creature entering causes a triggered ability of a permanent you control to trigger, that ability triggers an additional time.

Golden Argosy

Whenever Golden Argosy attacks, exile each creature that crewed it this turn. Return them to the battlefield tapped under their owner's control at the beginning of the next end step.
Crew 1 (Tap any number of creatures you control with total power 1 or more: This Vehicle becomes an artifact creature until end of turn.)

Archmage's Charm

Choose one —
• Counter target spell.
• Target player draws two cards.
• Gain control of target nonland permanent with mana value 1 or less.

Conjurer's Closet

At the beginning of your end step, you may exile target creature you control, then return that card to the battlefield under your control.

March of Swirling Mist

As an additional cost to cast this spell, you may exile any number of blue cards from your hand. This spell costs {2} less to cast for each card exiled this way.
Up to X target creatures phase out. (While they're phased out, they're treated as though they don't exist. Each one phases in before its controller untaps during their next untap step.)

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.

Murktide Regent

Delve (Each card you exile from your graveyard while casting this spell pays for {1}.)
Flying
Murktide Regent enters with a +1/+1 counter on it for each instant and sorcery card exiled with it.
Whenever an instant or sorcery card leaves your graveyard, put a +1/+1 counter on Murktide Regent.

Run Away Together

Choose two target creatures controlled by different players. Return those creatures to their owners' hands.

Archmage Emeritus

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

Teferi, Temporal Pilgrim

Whenever you draw a card, put a loyalty counter on Teferi, Temporal Pilgrim.
0: Draw a card.
−2: Create a 2/2 blue Spirit creature token with vigilance and "Whenever you draw a card, put a +1/+1 counter on this creature."
−12: Target opponent chooses a permanent they control and returns it to its owner's hand. Then they shuffle each nonland permanent they control into its owner's library.

Swiftfoot Boots

Equipped creature has hexproof and haste. (It can't be the target of spells or abilities your opponents control. It can attack and {T} no matter when it came under your control.)
Equip {1} ({1}: Attach to target creature you control. Equip only as a sorcery.)

Aetherize

Return all attacking creatures to their owner's hand.

Mischievous Mystic

Flying
Whenever you draw your second card each turn, create a 1/1 blue Faerie creature token with flying.

Aether Spike

Choose target spell. You get {E}{E} (two energy counters), then you may pay any amount of {E}. Counter that spell unless its controller pays {1} for each {E} paid this way.

Nezahal, Primal Tide

This spell can't be countered.
You have no maximum hand size.
Whenever an opponent casts a noncreature spell, draw a card.
Discard three cards: Exile Nezahal, Primal Tide. Return it to the battlefield tapped under its owner's control at the beginning of the next end step.

Temple of Cyclical Time

(Transforms from Ojer Pakpatiq, Deepest Epoch.)
{T}: Add {U}. Remove a time counter from Temple of Cyclical Time.
{2}{U}, {T}: Transform Temple of Cyclical Time. Activate only if it has no time counters on it and only as a sorcery.

Ojer Pakpatiq, Deepest Epoch

Flying
Whenever you cast an instant spell from your hand, it gains rebound. (Exile it as it resolves. At the beginning of your next upkeep, you may cast it from exile without paying its mana cost.)
When Ojer Pakpatiq dies, return it to the battlefield tapped and transformed under its owner's control with three time counters on it.

Ojer Pakpatiq, Deepest Epoch // Temple of Cyclical Time

Fleeting Distraction

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

Stormwing Entity

This spell costs {2}{U} less to cast if you've cast an instant or sorcery spell this turn.
Flying
Prowess (Whenever you cast a noncreature spell, this creature gets +1/+1 until end of turn.)
When Stormwing Entity enters, scry 2.

Serum Visions

Impede Momentum

Tap target creature and put three stun counters on it. (If a permanent with a stun counter would become untapped, remove one from it instead.)
Scry 1. (Look at the top card of your library. You may put that card on the bottom.)

Stormchaser's Talent

(Gain the next level as a sorcery to add its ability.)
When Stormchaser's Talent enters, create a 1/1 blue and red Otter creature token with prowess.
{3}{U}: Level 2
When this Class becomes level 2, return target instant or sorcery card from your graveyard to your hand.
{5}{U}: Level 3
Whenever you cast an instant or sorcery spell, create a 1/1 blue and red Otter creature token with prowess.

Jace Reawakened

You can't cast Jace Reawakened during your first, second, or third turns of the game.
+1: Draw a card, then discard a card.
+1: You may exile a nonland card with mana value 3 or less from your hand. If you do, it becomes plotted.
−6: Until end of turn, whenever you cast a spell, copy it. You may choose new targets for the copy.

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

Mind's Eye

Whenever an opponent draws a card, you may pay {1}. If you do, draw a card.

Curse of the Swine

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

Eluge, the Shoreless Sea

Eluge's power and toughness are each equal to the number of Islands you control.
Whenever Eluge enters or attacks, put a flood counter on target land. It's an Island in addition to its other types for as long as it has a flood counter on it.
The first instant or sorcery spell you cast each turn costs {U} (or {1}) less to cast for each land you control with a flood counter on it.

Island

Chart a Course

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

Security Bypass

Enchant creature
As long as enchanted creature is attacking alone, it can't be blocked.
Enchanted creature has "Whenever this creature deals combat damage to a player, it connives." (Its controller draws a card, then discards a card. If they discarded a nonland card, they put a +1/+1 counter on this creature.)

Sol Ring

Dour Port-Mage

Whenever one or more other creatures you control leave the battlefield without dying, draw a card.
{1}{U}, {T}: Return another target creature you control to its owner's hand.

Repulse

Return target creature to its owner's hand.
Draw a card.

Reliquary Tower

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

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.)

Ponder

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

Kiora, the Rising Tide

When Kiora enters, draw two cards, then discard two cards.
Threshold — Whenever Kiora attacks, if there are seven or more cards in your graveyard, you may create Scion of the Deep, a legendary 8/8 blue Octopus creature token.

Force of Will

You may pay 1 life and exile a blue card from your hand rather than pay this spell's mana cost.
Counter target spell.

Rhystic Study

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

High Fae Trickster

Flash (You may cast this spell any time you could cast an instant.)
Flying
You may cast spells as though they had flash.

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.")

Spellbook

Force of Negation

If it's not your turn, you may exile a blue card from your hand rather than pay this spell's mana cost.
Counter target noncreature spell. If that spell is countered this way, exile it instead of putting it into its owner's graveyard.

Mockingbird

Flying
You may have Mockingbird enter as a copy of any creature on the battlefield with mana value less than or equal to the amount of mana spent to cast Mockingbird, except it's a Bird in addition to its other types and it has flying.

Strix Lookout

Flying, vigilance (Attacking doesn't cause this creature to tap.)
{1}{U}, {T}: Draw a card, then discard a card.

Fblthp, the Lost

When Fblthp, the Lost enters, draw a card. If it entered from your library or was cast from your library, draw two cards instead.
When Fblthp becomes the target of a spell, shuffle Fblthp into its owner's library.

Fblthp, Lost on the Range

Ward {2}
You may look at the top card of your library any time.
The top card of your library has plot. The plot cost is equal to its mana cost.
You may plot nonland cards from the top of your library.

Displacer Kitten

Avoidance — Whenever you cast a noncreature spell, exile up to one target nonland permanent you control, then return that card to the battlefield under its owner's control.

Lunar Insight

Draw a card for each different mana value among nonland permanents you control.

Imprisoned in the Moon

Enchant creature, land, or planeswalker
Enchanted permanent is a colorless land with "{T}: Add {C}" and loses all other card types and abilities.

Sphinx of Forgotten Lore

Flash (You may cast this spell any time you could cast an instant.)
Flying
Whenever this creature attacks, target instant or sorcery card in your graveyard gains flashback until end of turn. The flashback cost is equal to that card's mana cost. (You may cast that card from your graveyard for its flashback cost. Then exile it.)

Think Twice

Draw a card.
Flashback {2}{U} (You may cast this card from your graveyard for its flashback cost. Then exile it.)

Windfall

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

Overlord of the Floodpits

Impending 4—{1}{U}{U} (If you cast this spell for its impending cost, it enters with four time counters and isn't a creature until the last is removed. At the beginning of your end step, remove a time counter from it.)
Flying
Whenever Overlord of the Floodpits enters or attacks, draw two cards, then discard a card.

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.

Chromatic Sphere

{1}, {T}, Sacrifice Chromatic Sphere: Add one mana of any color. Draw a card.

Compulsive Research

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

Subtlety

Flash
Flying
When Subtlety enters, choose up to one target creature spell or planeswalker spell. Its owner puts it on their choice of the top or bottom of their library.
Evoke—Exile a blue card from your hand.

Tezzeret's Gambit

({U/P} can be paid with either {U} or 2 life.)
Draw two cards, then proliferate. (Choose any number of permanents and/or players, then give each another counter of each kind already there.)

Homunculus Horde

Whenever you draw your second card each turn, create a token that's a copy of this creature.