Body of Knowledge

Body of Knowledge's power and toughness are each equal to the number of cards in your hand.
You have no maximum hand size.
Whenever this creature is dealt damage, draw that many cards.

Chasm Skulker

Whenever you draw a card, put a +1/+1 counter on this creature.
When this creature dies, create X 1/1 blue Squid creature tokens with islandwalk, where X is the number of +1/+1 counters on this creature. (They can't be blocked as long as defending player controls an Island.)

Proft's Eidetic Memory

When Proft's Eidetic Memory enters, draw a card.
You have no maximum hand size.
At the beginning of combat on your turn, if you've drawn more than one card this turn, put X +1/+1 counters on target creature you control, where X is the number of cards you've drawn this turn minus one.

High Tide

Until end of turn, whenever a player taps an Island for mana, that player adds an additional {U}.

Defiler of Dreams

Flying
As an additional cost to cast blue permanent spells, you may pay 2 life. Those spells cost {U} less to cast if you paid life this way. This effect reduces only the amount of blue mana you pay.
Whenever you cast a blue permanent spell, draw a card.

Lofty Denial

Counter target spell unless its controller pays {1}. If you control a creature with flying, counter that spell unless its controller pays {4} instead.

Emrakul's Messenger

Devoid (This card has no color.)
Flying
Whenever you draw your second card each turn, create a 0/1 colorless Eldrazi Spawn creature token with "Sacrifice this token: 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.)

Aqueous Form

Enchant creature
Enchanted creature can't be blocked.
Whenever enchanted creature attacks, scry 1. (Look at the top card of your library. You may put that card on the bottom.)

Run Away Together

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

Scour All Possibilities

Scry 2, then draw a card.
Flashback {4}{U} (You may cast this card from your graveyard for its flashback cost. Then exile it.)

Negate

Omen of the Sea

Flash (You may cast this spell any time you could cast an instant.)
When this enchantment enters, scry 2, then draw a card.
{2}{U}, Sacrifice this enchantment: 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.)

Cryptic Annelid

When this creature enters, scry 1, then scry 2, then scry 3. (To scry X, look at the top X cards of your library, then put any number of them on the bottom and the rest on top in any order.)

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.)

Mischievous Mystic

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

Island

Rivendell

Rivendell enters tapped unless you control a legendary creature.
{T}: Add {U}.
{1}{U}, {T}: Scry 2. Activate only if you control a legendary creature.

Teferi's Ageless Insight

If you would draw a card except the first one you draw in each of your draw steps, draw two cards instead.

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

Loyal Drake

Flying
Lieutenant — At the beginning of combat on your turn, if you control your commander, draw a card.

Sol Ring

Siani, Eye of the Storm

Flying
Whenever Siani attacks, scry X, where X is the number of attacking creatures with flying.
Partner (You can have two commanders if both have partner.)

Augury Owl

Flying
When this creature enters, scry 3. (Look at the top three cards of your library, then put any number of them on the bottom and the rest on top in any order.)

Gravitational Shift

Creatures with flying get +2/+0.
Creatures without flying get -2/-0.

Thassa, God of the Sea

Indestructible
As long as your devotion to blue is less than five, Thassa isn't a creature. (Each {U} in the mana costs of permanents you control counts toward your devotion to blue.)
At the beginning of your upkeep, scry 1.
{1}{U}: Target creature you control can't be blocked this turn.

Faerie Seer

Flying
When this creature enters, 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.)

Tamiyo's Epiphany

Oneirophage

Flying
Whenever you draw a card, put a +1/+1 counter on this creature.

Arcane Signet

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

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.")

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.

Mystic Sanctuary

({T}: Add {U}.)
This land enters tapped unless you control three or more other Islands.
When this land enters untapped, you may put target instant or sorcery card from your graveyard on top of your library.

Arcane Denial

Counter target spell. Its controller may draw up to two cards at the beginning of the next turn's upkeep.
You draw a card at the beginning of the next turn's upkeep.

Silver Raven

Flying
When this creature enters, scry 1. (Look at the top card of your library. You may put that card on the bottom.)

Eligeth, Crossroads Augur

Flying
If you would scry a number of cards, draw that many cards instead.
Partner (You can have two commanders if both have partner.)

Bane's Contingency

Counter target spell. If that spell targets a commander you control, instead counter that spell, scry 2, then draw a card.

Behold the Multiverse

Scry 2, then draw two cards.
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.)

Kira, Great Glass-Spinner

Flying
Creatures you control have "Whenever this creature becomes the target of a spell or ability for the first time each turn, counter that spell or ability."

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 this creature.

Ornithopter of Paradise

Serum Sovereign

Flying
Whenever you cast a noncreature spell, put an oil counter on this creature.
{U}, Remove an oil counter from this creature: Draw a card, then scry 2.

Pongify

Destroy target creature. It can't be regenerated. Its controller creates a 3/3 green Ape creature token.

Windreader Sphinx

Flying
Whenever a creature with flying attacks, you may draw a card.

Dissolve

Counter target spell. Scry 1. (Look at the top card of your library. You may put that card on the bottom.)

Favorable Winds

Creatures you control with flying get +1/+1.

Esior, Wardwing Familiar

Flying
Spells your opponents cast that target one or more commanders you control cost {3} more to cast.
Partner (You can have two commanders if both have partner.)

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.)

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.

Sphinx of Foresight

You may reveal this card from your opening hand. If you do, scry 3 at the beginning of your first upkeep.
Flying
At the beginning of your upkeep, scry 1.

Archetype of Imagination

Creatures you control have flying.
Creatures your opponents control lose flying and can't have or gain flying.

Resculpt

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

Frantic Search

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

Counterspell

Psychosis Crawler

Psychosis Crawler's power and toughness are each equal to the number of cards in your hand.
Whenever you draw a card, each opponent loses 1 life.

Sapphire Medallion

Blue spells you cast cost {1} less to cast.

Thought Vessel

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

Warden of Evos Isle

Flying
Creature spells with flying you cast cost {1} less to cast.

Foresee

Prognostic Sphinx

Flying
Discard a card: This creature gains hexproof until end of turn. Tap it.
Whenever this creature attacks, scry 3.

Reliquary Tower

Clinquant Skymage

Deliberate

Decanter of Endless Water

You have no maximum hand size.
{T}: Add one mana of any color.

Aetherize

Return all attacking creatures to their owner's hand.

Serum Visions

Siren Stormtamer

Flying
{U}, Sacrifice this creature: Counter target spell or ability that targets you or a creature you control.