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.

Aven Trooper

Flying
{2}{W}, Discard a card: Aven Trooper gets +1/+2 until end of turn.

Aven Fisher

Flying (This creature can't be blocked except by creatures with flying or reach.)
When Aven Fisher dies, you may draw a card.

Battleflight Eagle

Flying
When Battleflight Eagle enters, target creature gets +2/+2 and gains flying until end of turn.

Coastal Hornclaw

Sacrifice a land: Coastal Hornclaw gains flying until end of turn.

Koilos Roc

Flash
Flying
When Koilos Roc enters, create a tapped Powerstone token. (It's an artifact with "{T}: Add {C}. This mana can't be spent to cast a nonartifact spell.")

Eagle of the Watch

Stormwatch Eagle

Flying
Sacrifice a land: Return Stormwatch Eagle to its owner's hand.

Aven Reedstalker

Rustwing Falcon

Carrier Pigeons

Flying
When Carrier Pigeons enters, draw a card at the beginning of the next turn's upkeep.

Kenku Artificer

Homunculus Servant — When Kenku Artificer enters, put three +1/+1 counters on up to one target noncreature artifact. That artifact becomes a 0/0 Homunculus artifact creature with flying.

Crookclaw Elder

Flying
Tap two untapped Birds you control: Draw a card.
Tap two untapped Wizards you control: Target creature gains flying until end of turn.

Tah-Crop Elite

Flying
You may exert Tah-Crop Elite as it attacks. When you do, creatures you control get +1/+1 until end of turn. (An exerted creature won't untap during your next untap step.)

Aven Flock

Flying (This creature can't be blocked except by creatures with flying or reach.)
{W}: Aven Flock gets +0/+1 until end of turn.

Kingfisher

Flying
When Kingfisher dies, draw a card.

Battlefield Raptor

Mystic Familiar

Flying
Threshold — As long as seven or more cards are in your graveyard, Mystic Familiar gets +1/+1 and has protection from black.

Gustcloak Skirmisher

Flying
Whenever Gustcloak Skirmisher becomes blocked, you may untap it and remove it from combat.

Harrier Strix

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

Aven Battle Priest

Flying (This creature can't be blocked except by creatures with flying or reach.)
When Aven Battle Priest enters, you gain 3 life.

Airborne Aid

Draw a card for each Bird on the battlefield.

Supply-Line Cranes

Flying
When Supply-Line Cranes enters, put a +1/+1 counter on target creature.

Aven of Enduring Hope

Flying
When Aven of Enduring Hope enters, you gain 3 life.

Aarakocra Sneak

Flying
When Aarakocra Sneak enters, you take the initiative.

Coast Watcher

Aven Envoy

Sterling Supplier

Flying
When Sterling Supplier enters, put a +1/+1 counter on another target creature you control.

Strix Lookout

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

Aven Initiate

Flying
Embalm {6}{U} ({6}{U}, Exile this card from your graveyard: Create a token that's a copy of it, except it's a white Zombie Bird Warrior with no mana cost. Embalm only as a sorcery.)

Preening Champion

Flying
When Preening Champion enters, create a 1/1 blue and red Elemental creature token.

Seller of Songbirds

When Seller of Songbirds enters, create a 1/1 white Bird creature token with flying.

Speakeasy Server

Flying
When Speakeasy Server enters, you gain 1 life for each other creature you control.

Aven Windreader

Flying (This creature can't be blocked except by creatures with flying or reach.)
{1}{U}: Target player reveals the top card of their library.