Angelic Wall

Defender (This creature can't attack.)
Flying

Augury Owl

Flying
When Augury Owl enters the battlefield, scry 3. (Look at the top three cards of your library, then put any number of them on the bottom of your library and the rest on top in any order.)

Aven Fogbringer

Flying
When Aven Fogbringer enters the battlefield, return target land to its owner's hand.

Watcher of the Spheres

Flying
Creature spells with flying you cast cost {1} less to cast.
Whenever another creature with flying enters the battlefield under your control, Watcher of the Spheres gets +1/+1 until end of turn.