Verity Circle

Whenever a creature an opponent controls becomes tapped, if it isn't being declared as an attacker, you may draw a card.
{4}{U}: Tap target creature without flying.

Empyrean Eagle

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

Elite Guardmage

Flying
When Elite Guardmage enters, you gain 3 life and draw a card.

Mu Yanling, Celestial Wind

+1: Until your next turn, up to one target creature gets -5/-0.
−3: Return up to two target creatures to their owners' hands.
−7: Creatures you control with flying get +5/+5 until end of turn.

Dovin's Veto

This spell can't be countered.
Counter target noncreature spell.

Warden of Evos Isle

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

Plains

Deputy of Detention

When Deputy of Detention enters, exile target nonland permanent an opponent controls and all other nonland permanents that player controls with the same name as that permanent until Deputy of Detention leaves the battlefield.

Favorable Winds

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

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.

Windstorm Drake

Flying
Other creatures you control with flying get +1/+0.

Azorius Guildgate

Azorius Guildgate enters tapped.
{T}: Add {W} or {U}.

Dream Trawler

Flying, lifelink
Whenever you draw a card, Dream Trawler gets +1/+0 until end of turn.
Whenever Dream Trawler attacks, draw a card.
Discard a card: Dream Trawler gains hexproof until end of turn. Tap it.

Meandering River

Meandering River enters tapped.
{T}: Add {W} or {U}.

Kasmina's Transmutation

Enchant creature
Enchanted creature loses all abilities and has base power and toughness 1/1.

Gravitational Shift

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

Aerial Assault

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

Rally of Wings

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

Island

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.