Plains

Favorable Winds

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

Healer's Hawk

Flying
Lifelink (Damage dealt by this creature also causes you to gain that much life.)

Island

Migratory Route

Create four 1/1 white Bird creature tokens with flying.
Basic landcycling {2} ({2}, Discard this card: Search your library for a basic land card, reveal it, put it into your hand, then shuffle.)

Forest

Aerial Assault

Destroy target tapped creature. You gain 1 life for each creature you control with flying.

Empyrean Eagle

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

Thornwood Falls

This land enters tapped.
When this land enters, you gain 1 life.
{T}: Add {G} or {U}.

Seaside Citadel

This land enters tapped.
{T}: Add {G}, {W}, or {U}.

Evolving Wilds

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

Gust of Wind

This spell costs {2} less to cast if you control a creature with flying.
Return target nonland permanent you don't control to its owner's hand.
Draw a card.

Winged Words

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

Colorful Feiyi Sparrow

Flying (This creature can't be blocked except by creatures with flying or reach.)

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.

Tranquil Cove

This land enters tapped.
When this land enters, you gain 1 life.
{T}: Add {W} or {U}.

River Hoopoe

Flying
{3}{G}{U}: You gain 2 life and draw a card.

Birds of Paradise

Gilded Goose

Flying
When this creature enters, create a Food token. (It's an artifact with "{2}, {T}, Sacrifice this token: You gain 3 life.")
{1}{G}, {T}: Create a Food token.
{T}, Sacrifice a Food: Add one mana of any color.