Rhystic Study

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

Linvala, Shield of Sea Gate

Flying
At the beginning of combat on your turn, if you have a full party, choose target nonland permanent an opponent controls. Until your next turn, it can't attack or block, and its activated abilities can't be activated.
Sacrifice Linvala: Choose hexproof or indestructible. Creatures you control gain that ability until end of turn.

Empyrean Eagle

Flying
Other creatures you control with flying get +1/+1.

Silver Myr

Gravitational Shift

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

Island

Stroke of Midnight

Destroy target nonland permanent. Its controller creates a 1/1 white Human creature token.

Talisman of Progress

{T}: Add {C}.
{T}: Add {W} or {U}. Talisman of Progress deals 1 damage to you.

Ever-Watching Threshold

Whenever an opponent attacks, if they attacked you and/or a planeswalker you control, draw a card.

Suppressor Skyguard

Flying
Whenever a player attacks you, if that player has another opponent who isn't being attacked, prevent all combat damage that would be dealt to you this combat.

Skycat Sovereign

Flying
Skycat Sovereign gets +1/+1 for each other creature you control with flying.
{2}{W}{U}: Create a 1/1 white Cat Bird creature token with flying.

Kangee's Lieutenant

Flying
Whenever Kangee's Lieutenant attacks, attacking creatures with flying get +1/+1 until end of turn.
Encore {5}{W} ({5}{W}, Exile this card from your graveyard: For each opponent, create a token copy that attacks that opponent this turn if able. They gain haste. Sacrifice them at the beginning of the next end step. Activate only as a sorcery.)

Arcane Signet

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

Oracle's Insight

Enchant creature
Enchanted creature has "{T}: Scry 1, then draw a card." (To scry 1, look at the top card of your library, then you may put that card on the bottom.)

Emeria Angel

Flying
Landfall — Whenever a land you control enters, you may create a 1/1 white Bird creature token with flying.

Malleable Impostor

Flash
Flying
You may have Malleable Impostor enter as a copy of a creature an opponent controls, except it's a Faerie Shapeshifter in addition to its other types and it has flying.

Grand Arbiter Augustin IV

White spells you cast cost {1} less to cast.
Blue spells you cast cost {1} less to cast.
Spells your opponents cast cost {1} more to cast.

Consider

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

As Foretold

At the beginning of your upkeep, put a time counter on As Foretold.
Once each turn, you may pay {0} rather than pay the mana cost for a spell you cast with mana value X or less, where X is the number of time counters on As Foretold.

Cloudfin Raptor

Flying
Evolve (Whenever a creature you control enters, if that creature has greater power or toughness than this creature, put a +1/+1 counter on this creature.)

Terramorphic Expanse

{T}, Sacrifice Terramorphic Expanse: Search your library for a basic land card, put it onto the battlefield tapped, then shuffle.

Sunblast Angel

Flying
When Sunblast Angel enters, destroy all tapped creatures.

Curiosity

Enchant creature
Whenever enchanted creature deals damage to an opponent, you may draw a card.

Watcher of the Spheres

Flying
Creature spells with flying you cast cost {1} less to cast.
Whenever another creature you control with flying enters, Watcher of the Spheres gets +1/+1 until end of turn.

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."

Sunscorch Regent

Flying
Whenever an opponent casts a spell, put a +1/+1 counter on Sunscorch Regent and you gain 1 life.

True Conviction

Creatures you control have double strike and lifelink.

Favorable Winds

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

Bubble Snare

Kicker {2}{U} (You may pay an additional {2}{U} as you cast this spell.)
Enchant creature
When Bubble Snare enters, if it was kicked, tap enchanted creature.
Enchanted creature doesn't untap during its controller's untap step.

Hallowed Fountain

({T}: Add {W} or {U}.)
As Hallowed Fountain enters, you may pay 2 life. If you don't, it enters tapped.

Spellbook

Kangee, Sky Warden

Flying, vigilance
Whenever Kangee, Sky Warden attacks, attacking creatures with flying get +2/+0 until end of turn.
Whenever Kangee blocks, blocking creatures with flying get +0/+2 until end of turn.

Mind Stone

{T}: Add {C}.
{1}, {T}, Sacrifice Mind Stone: Draw a card.

Triumphant Reckoning

Return all artifact, enchantment, and planeswalker cards from your graveyard to the battlefield.

Rally of Wings

Untap all creatures you control. Creatures you control with flying get +2/+2 until end of turn.

Unbreakable Formation

Creatures you control gain indestructible until end of turn.
Addendum — If you cast this spell during your main phase, put a +1/+1 counter on each of those creatures and they gain vigilance until end of turn.

Grey Host Reinforcements

Flying, ward {3}
When Grey Host Reinforcements enters, exile target player's graveyard. Put a number of +1/+1 counters on Grey Host Reinforcements equal to the number of creature cards exiled this way.

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.)

Loyal Drake

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

Scheming Fence

As Scheming Fence enters, you may choose a nonland permanent.
Activated abilities of the chosen permanent can't be activated.
Scheming Fence has all activated abilities of the chosen permanent except for loyalty abilities. You may spend mana as though it were mana of any color to activate those abilities.

Steel-Plume Marshal

Flying
Whenever Steel-Plume Marshal attacks, other attacking creatures you control with flying get +2/+2 until end of turn.

Archon of Redemption

Flying
Whenever Archon of Redemption or another creature you control with flying enters, you may gain life equal to that creature's power.

Command Tower

Swords to Plowshares

Exile target creature. Its controller gains life equal to its power.

Aetherize

Return all attacking creatures to their owner's hand.

Eaten by Piranhas

Flash (You may cast this spell any time you could cast an instant.)
Enchant creature
Enchanted creature loses all abilities and is a black Skeleton creature with base power and toughness 1/1. (It loses all other colors, card types, and creature types.)

Archetype of Imagination

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

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.

Warden of Evos Isle

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

Counterspell

Gold Myr

Sol Ring

Glacial Fortress

Glacial Fortress enters tapped unless you control a Plains or an Island.
{T}: Add {W} or {U}.

The Immortal Sun

Players can't activate planeswalkers' loyalty abilities.
At the beginning of your draw step, draw an additional card.
Spells you cast cost {1} less to cast.
Creatures you control get +1/+1.

Path of Ancestry

Path of Ancestry enters tapped.
{T}: Add one mana of any color in your commander's color identity. When that mana is spent to cast a creature spell that shares a creature type with your commander, scry 1. (Look at the top card of your library. You may put that card on the bottom.)

Liquimetal Torque

{T}: Add {C}.
{T}: Target nonland permanent becomes an artifact in addition to its other types until end of turn.

Judge's Familiar

Flying
Sacrifice Judge's Familiar: Counter target instant or sorcery spell unless its controller pays {1}.

Winged Words

This spell costs {1} less to cast if you control a creature with flying.
Draw two cards.

Sephara, Sky's Blade

You may pay {W} and tap four untapped creatures you control with flying rather than pay this spell's mana cost.
Flying, lifelink
Other creatures you control with flying have indestructible. (Damage and effects that say "destroy" don't destroy them.)

Dictate of Heliod

Smothering Tithe

Whenever an opponent draws a card, that player may pay {2}. If the player doesn't, you create a Treasure token. (It's an artifact with "{T}, Sacrifice this artifact: Add one mana of any color.")

Azorius Chancery

Azorius Chancery enters tapped.
When Azorius Chancery enters, return a land you control to its owner's hand.
{T}: Add {W}{U}.

Evolving Wilds

{T}, Sacrifice this land: Search your library for a basic land card, put it onto the battlefield tapped, then shuffle.

Fellwar Stone

{T}: Add one mana of any color that a land an opponent controls could produce.

Reliquary Tower

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

Always Watching

Nontoken creatures you control get +1/+1 and have vigilance.

Negate

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.

Magus of the Moat

Port Town

As Port Town enters, you may reveal a Plains or Island card from your hand. If you don't, Port Town enters tapped.
{T}: Add {W} or {U}.

Windbrisk Heights

Hideaway 4 (When this land enters, look at the top four cards of your library, exile one face down, then put the rest on the bottom in a random order.)
Windbrisk Heights enters tapped.
{T}: Add {W}.
{W}, {T}: You may play the exiled card without paying its mana cost if you attacked with three or more creatures this turn.

Prairie Stream

({T}: Add {W} or {U}.)
Prairie Stream enters tapped unless you control two or more basic lands.

Azorius Signet

Thought Vessel

Ornithopter of Paradise

Plains

Medomai the Ageless

Flying
Whenever Medomai the Ageless deals combat damage to a player, take an extra turn after this one.
Medomai the Ageless can't attack during extra turns.

Sky Diamond

Esper Sentinel

Whenever an opponent casts their first noncreature spell each turn, draw a card unless that player pays {X}, where X is Esper Sentinel's power.