Deadly Dispute

As an additional cost to cast this spell, sacrifice an artifact or creature.
Draw two cards and create a Treasure token. (It's an artifact with "{T}, Sacrifice this token: Add one mana of any color.")

Impaler Shrike

Flying
Whenever this creature deals combat damage to a player, you may sacrifice it. If you do, draw three cards.

Jackdaw Savior

Flying
Whenever this creature or another creature you control with flying dies, return another target creature card with lesser mana value from your graveyard to the battlefield.

Murmuring Mystic

Whenever you cast an instant or sorcery spell, create a 1/1 blue Bird Illusion creature token with flying.

Airborne Aid

Draw a card for each Bird on the battlefield.

Thrummingbird

Flying
Whenever this creature deals combat damage to a player, proliferate. (Choose any number of permanents and/or players, then give each another counter of each kind already there.)

Island

Wingmantle Chaplain

Defender
When this creature enters, create a 1/1 white Bird creature token with flying for each creature with defender you control.
Whenever another creature you control with defender enters, create a 1/1 white Bird creature token with flying.

Seaside Haven

{T}: Add {C}.
{W}{U}, {T}, Sacrifice a Bird: Draw a card.

Kastral, the Windcrested

Flying
Whenever one or more Birds you control deal combat damage to a player, choose one —
• You may put a Bird creature card from your hand or graveyard onto the battlefield with a finality counter on it.
• Put a +1/+1 counter on each Bird you control.
• Draw a card.

Squadron Hawk

Flying
When this creature enters, you may search your library for up to three cards named Squadron Hawk, reveal them, put them into your hand, then shuffle.

Lifecreed Duo

Flying
Whenever another creature you control enters, you gain 1 life.

Orator of Ojutai

As an additional cost to cast this spell, you may reveal a Dragon card from your hand.
Defender, flying
When this creature enters, if you revealed a Dragon card or controlled a Dragon as you cast this spell, draw a card.

Plains

Village Rites

As an additional cost to cast this spell, sacrifice a creature.
Draw two cards.

Corrupted Conviction

Nesting Dovehawk

Flying
At the beginning of combat on your turn, populate. (Create a token that's a copy of a creature token you control.)
Whenever a creature token you control enters, put a +1/+1 counter on this creature.

Return to Action

Until end of turn, target creature gets +1/+0 and gains lifelink and "When this creature dies, return it to the battlefield tapped under its owner's control."

Healer's Hawk

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

Monastery Flock

Defender, flying
Morph {U} (You may cast this card face down as a 2/2 creature for {3}. Turn it face up any time for its morph cost.)

Augury Owl

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

Gwaihir the Windlord

This spell costs {2} less to cast as long as you've drawn two or more cards this turn.
Flying, vigilance
Other Birds you control have vigilance.

Bone Splinters

As an additional cost to cast this spell, sacrifice a creature.
Destroy target creature.

Blur

Exile target creature you control, then return that card to the battlefield under its owner's control.
Draw a card.

Feast of the Victorious Dead

At the beginning of your end step, if one or more creatures died this turn, you gain that much life and distribute that many +1/+1 counters among creatures you control.

Fake Your Own Death

Until end of turn, target creature gets +2/+0 and gains "When this creature dies, return it to the battlefield tapped under its owner's control and you create a Treasure token." (It's an artifact with "{T}, Sacrifice this token: Add one mana of any color.")

Roc Egg

Defender (This creature can't attack.)
When this creature dies, create a 3/3 white Bird creature token with flying.

Ephemerate

Exile target creature you control, then return it to the battlefield under its owner's control.
Rebound (If you cast this spell from your hand, exile it as it resolves. At the beginning of your next upkeep, you may cast this card from exile without paying its mana cost.)

Acrobatic Maneuver

Warden of Evos Isle

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

Soulcatchers' Aerie

Whenever a Bird is put into your graveyard from the battlefield, put a feather counter on this enchantment.
Bird creatures get +1/+1 for each feather counter on this enchantment.

Keeper of the Nine Gales

Flying
{T}, Tap two untapped Birds you control: Return target permanent to its owner's hand.

Emeria Angel

Flying
Landfall — Whenever a land you control enters, you may create a 1/1 white Bird creature token with flying.

Plumecreed Mentor

Flying
Whenever this creature or another creature you control with flying enters, put a +1/+1 counter on target creature you control without flying.

Battle Screech

Create two 1/1 white Bird creature tokens with flying.
Flashback—Tap three untapped white creatures you control. (You may cast this card from your graveyard for its flashback cost. Then exile it.)