Watcher of the Spheres

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

Thunderclap Wyvern

Flash (You may cast this spell any time you could cast an instant.)
Flying
Other creatures you control with flying get +1/+1.

Hushbringer

Flying, lifelink
Creatures entering or dying don't cause abilities to trigger.

Inniaz, the Gale Force

Flying
{2}{W/U}: Attacking creatures with flying get +1/+1 until end of turn. ({W/U} can be paid with either {W} or {U}.)
Whenever three or more creatures you control with flying attack, each player gains control of a nonland permanent of your choice controlled by the player to their right.

Thraben Watcher

Flying, vigilance
Other nontoken creatures you control get +1/+1 and have vigilance.

Warden of Evos Isle

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

Ornithopter

Jubilant Skybonder

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

Thieving Skydiver

Kicker {X}. X can't be 0. (You may pay an additional {X} as you cast this spell.)
Flying
When this creature enters, if it was kicked, gain control of target artifact with mana value X or less. If that artifact is an Equipment, attach it to this creature.

Emeria Angel

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

Kinjalli's Sunwing

Flying
Creatures your opponents control enter tapped.

Donal, Herald of Wings

Whenever you cast a nonlegendary creature spell with flying, you may copy it, except the copy is a 1/1 Spirit in addition to its other types. Do this only once each turn. (The copy becomes a token.)

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.)

Skycat Sovereign

Flying
This creature 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.

Empyrean Eagle

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

Favorable Winds

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

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."

Magus of the Moat

Errant and Giada

Flash
Flying
You may look at the top card of your library any time.
You may cast spells with flash or flying from the top of your library.

Kangee, Sky Warden

Flying, vigilance
Whenever Kangee 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.

Pride of the Clouds

Flying
This creature gets +1/+1 for each other creature on the battlefield with flying.
Forecast — {2}{W}{U}, Reveal this creature from your hand: Create a 1/1 white and blue Bird creature token with flying. (Activate only during your upkeep and only once each turn.)

Ornithopter of Paradise

Dovescape

({W/U} can be paid with either {W} or {U}.)
Whenever a player casts a noncreature spell, counter that spell. That player creates X 1/1 white and blue Bird creature tokens with flying, where X is the spell's mana value.

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.)