Dungeon Geists

Flying
When this creature enters, tap target creature an opponent controls. That creature doesn't untap during its controller's untap step for as long as you control this creature.

Winged Words

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

Frost Lynx

When this creature enters, tap target creature an opponent controls. That creature doesn't untap during its controller's next untap step.

Unsummon

Return target creature to its owner's hand.

Waterkin Shaman

Whenever a creature you control with flying enters, this creature gets +1/+1 until end of turn.

Spectral Sailor

Flash (You may cast this spell any time you could cast an instant.)
Flying
{3}{U}: Draw a card.

Island

Air Elemental

Cloudkin Seer

Flying
When this creature enters, 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.

Riddlemaster Sphinx

Flying (This creature can't be blocked except by creatures with flying or reach.)
When this creature enters, you may return target creature an opponent controls to its owner's hand.

Warden of Evos Isle

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

Celestial Messenger

Flash (You may cast this card any time you could cast an instant.)
Flying
This creature gets +1/+1 as long as you control a Yanling planeswalker.

Yanling's Harbinger

Flying
When this creature enters, you may search your library and/or graveyard for a card named Mu Yanling, Celestial Wind, reveal it, and put it into your hand. If you search your library this way, shuffle.

Brineborn Cutthroat

Flash (You may cast this spell any time you could cast an instant.)
Whenever you cast a spell during an opponent's turn, put a +1/+1 counter on this creature.