Jubilant Skybonder

Flying
Creatures you control with flying have "Spells your opponents cast that target this creature cost {2} more to cast."

Steel-Plume Marshal

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

Island

Pearl Medallion

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

Magus of the Moat

Flood

{U}{U}: Tap target creature without flying.

Azorius Charm

Choose one —
• Creatures you control gain lifelink until end of turn.
• Draw a card.
• Put target attacking or blocking creature on top of its owner's library.

Kastral, the Windcrested

Flying
Whenever one or more Birds you control deal combat damage to a player, choose one —
• You may put a Bird creature card from your hand or graveyard onto the battlefield with a finality counter on it.
• Put a +1/+1 counter on each Bird you control.
• Draw a card.

Kindred Discovery

As Kindred Discovery enters, choose a creature type.
Whenever a creature you control of the chosen type enters or attacks, draw a card.

Harrier Strix

Flying
When Harrier Strix enters, tap target permanent.
{2}{U}: Draw a card, then discard a card.

Judge's Familiar

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

Plains

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.

Azorius Chancery

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

Coat of Arms

Each creature gets +1/+1 for each other creature on the battlefield that shares at least one creature type with it. (For example, if two Goblin Warriors and a Goblin Shaman are on the battlefield, each gets +2/+2.)

Aven Sunstriker

Flying
Double strike (This creature deals both first-strike and regular combat damage.)
Megamorph {4}{W} (You may cast this card face down as a 2/2 creature for {3}. Turn it face up any time for its megamorph cost and put a +1/+1 counter on it.)

Arcane Signet

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

Talisman of Progress

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

Aven Interrupter

Flash
Flying
When Aven Interrupter enters, exile target spell. It becomes plotted. (Its owner may cast it as a sorcery on a later turn without paying its mana cost.)
Spells your opponents cast from graveyards or from exile cost {2} more to cast.

Gwaihir the Windlord

This spell costs {2} less to cast as long as you've drawn two or more cards this turn.
Flying, vigilance
Other Birds you control have vigilance.

Military Intelligence

Whenever you attack with two or more creatures, draw a card.

Vanquisher's Banner

As Vanquisher's Banner enters, choose a creature type.
Creatures you control of the chosen type get +1/+1.
Whenever you cast a creature spell of the chosen type, draw a card.

Warden of Evos Isle

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

Exotic Orchard

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

Thieving Magpie

Flying (This creature can't be blocked except by creatures with flying or reach.)
Whenever Thieving Magpie deals damage to an opponent, draw a card.

Ishai, Ojutai Dragonspeaker

Flying
Whenever an opponent casts a spell, put a +1/+1 counter on Ishai, Ojutai Dragonspeaker.
Partner (You can have two commanders if both have partner.)

Reliquary Tower

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

Aven Mindcensor

Flash
Flying
If an opponent would search a library, that player searches the top four cards of that library instead.

Lieutenant Kirtar

Flying
{1}{W}, Sacrifice Lieutenant Kirtar: Exile target attacking creature.

Urza's Incubator

As Urza's Incubator enters, choose a creature type.
Creature spells of the chosen type cost {2} less to cast.

Azorius Keyrune

{T}: Add {W} or {U}.
{W}{U}: Azorius Keyrune becomes a 2/2 white and blue Bird artifact creature with flying until end of turn.

True Conviction

Creatures you control have double strike and lifelink.

Glacial Fortress

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

Seaside Haven

{T}: Add {C}.
{W}{U}, {T}, Sacrifice a Bird: Draw a card.

Aerial Extortionist

Flying
Whenever Aerial Extortionist enters or deals combat damage to a player, exile up to one target nonland permanent. For as long as that card remains exiled, its owner may cast it.
Whenever another player casts a spell from anywhere other than their hand, draw a card.

Propaganda

Creatures can't attack you unless their controller pays {2} for each creature they control that's attacking you.

Vexing Radgull

Flying
Whenever Vexing Radgull deals combat damage to a player, that player gets two rad counters if they don't have any rad counters. Otherwise, proliferate. (Choose any number of permanents and/or players, then give each another counter of each kind already there.)

Rhystic Study

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

Favorable Winds

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

Tidal Flats

{U}{U}: For each attacking creature without flying, its controller may pay {1}. If that player doesn't, creatures you control blocking that creature gain first strike until end of turn.

Mu Yanling, Sky Dancer

+2: Until your next turn, up to one target creature gets -2/-0 and loses flying.
−3: Create a 4/4 blue Elemental Bird creature token with flying.
−8: You get an emblem with "Islands you control have '{T}: Draw a card.'"

Aboshan, Cephalid Emperor

Tap an untapped Octopus you control: Tap target permanent.
{U}{U}{U}: Tap all creatures without flying.

Sol Ring

Animal Sanctuary

{T}: Add {C}.
{2}, {T}: Put a +1/+1 counter on target Bird, Cat, Dog, Goat, Ox, or Snake.

Healer's Hawk

Ghostly Prison

Thought Vessel

Airborne Aid

Draw a card for each Bird on the battlefield.

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.)

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.

Sawtooth Loon

Flying
When Sawtooth Loon enters, return a white or blue creature you control to its owner's hand.
When Sawtooth Loon enters, draw two cards, then put two cards from your hand on the bottom of your library.

Aven Gagglemaster

Flying
When Aven Gagglemaster enters, you gain 2 life for each creature you control with flying.

Idyllic Beachfront

({T}: Add {W} or {U}.)
Idyllic Beachfront enters tapped.

Gravitational Shift

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

Floodgate

Defender
When Floodgate has flying, sacrifice it.
When Floodgate leaves the battlefield, it deals damage to each nonblue creature without flying equal to half the number of Islands you control, rounded down.

Deluge

Battlefield Raptor

Hallowed Fountain

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

Command Tower

Curiosity Crafter

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

Cartographer's Hawk

Flying
When Cartographer's Hawk deals combat damage to a player who controls more lands than you, return it to its owner's hand. If you do, you may search your library for a Plains card, put it onto the battlefield tapped, then shuffle.

Path to Exile

Exile target creature. Its controller may search their library for a basic land card, put that card onto the battlefield tapped, then shuffle.

Thrummingbird

Flying
Whenever Thrummingbird deals combat damage to a player, proliferate. (Choose any number of permanents and/or players, then give each another counter of each kind already there.)

Arctic Aven

Flying
Arctic Aven gets +1/+1 as long as you control a Plains.
{W}: Arctic Aven gains lifelink until end of turn. (Damage dealt by this creature also causes you to gain that much life.)

Sapphire Medallion

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

Swords to Plowshares

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

Cloudchaser Kestrel

Flying
When Cloudchaser Kestrel enters, destroy target enchantment.
{W}: Target permanent becomes white until end of turn.

Soulcatchers' Aerie

Whenever a Bird is put into your graveyard from the battlefield, put a feather counter on Soulcatchers' Aerie.
Bird creatures get +1/+1 for each feather counter on Soulcatchers' Aerie.

Skymark Roc

Flying
Whenever Skymark Roc attacks, you may return target creature defending player controls with toughness 2 or less to its owner's hand.

Decanter of Endless Water

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

Empyrean Eagle

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

Yorion, Sky Nomad

Companion — Your starting deck contains at least twenty cards more than the minimum deck size. (If this card is your chosen companion, you may put it into your hand from outside the game for {3} as a sorcery.)
Flying
When Yorion enters, exile any number of other nonland permanents you own and control. Return those cards to the battlefield at the beginning of the next end step.