Aetherstorm Roc

Flying
Whenever this creature or another creature you control enters, you get {E} (an energy counter).
Whenever this creature attacks, you may pay {E}{E}. If you do, put a +1/+1 counter on it and tap up to one target creature defending player controls.

Apex Hawks

Multikicker {1}{W} (You may pay an additional {1}{W} any number of times as you cast this spell.)
Flying
This creature enters with a +1/+1 counter on it for each time it was kicked.

Plains

Birds of Paradise

Derevi, Empyrial Tactician

Flying
When Derevi enters and whenever a creature you control deals combat damage to a player, you may tap or untap target permanent.
{1}{G}{W}{U}: Put Derevi onto the battlefield from the command zone.

Airborne Aid

Draw a card for each Bird on the battlefield.

Forest

Abzan Skycaptain

Flying
When this creature dies, bolster 2. (Choose a creature with the least toughness among creatures you control and put two +1/+1 counters on it.)

Call

Create four 1/1 white Bird creature tokens with flying.
Fuse (You may cast one or both halves of this card from your hand.)

Beck

Whenever a creature enters this turn, you may draw a card.
Fuse (You may cast one or both halves of this card from your hand.)

Beck // Call

Arcanist's Owl

Flying
When this creature enters, look at the top four cards of your library. You may reveal an artifact or enchantment card from among them and put it into your hand. Put the rest on the bottom of your library in a random order.