Bird

Duskmourn: House of Horror Commander Tokens

Bloomburrow Commander Tokens

Modern Horizons 3 Tokens

Outlaws of Thunder Junction Tokens

Riku of Many Paths

Whenever you cast a modal spell, choose up to X, where X is the number of times you chose a mode for that spell —
• Exile the top card of your library. Until the end of your next turn, you may play it.
• Put a +1/+1 counter on Riku of Many Paths. It gains trample until end of turn.
• Create a 1/1 blue Bird creature token with flying.

Ravenform

Exile target artifact or creature. Its controller creates a 1/1 blue Bird creature token with flying.
Foretell {U} (During your turn, you may pay {2} and exile this card from your hand face down. Cast it on a later turn for its foretell cost.)

Alrund's Epiphany

Create two 1/1 blue Bird creature tokens with flying. Take an extra turn after this one. Exile Alrund's Epiphany.
Foretell {4}{U}{U} (During your turn, you may pay {2} and exile this card from your hand face down. Cast it on a later turn for its foretell cost.)

The Raven's Warning

(As this Saga enters and after your draw step, add a lore counter. Sacrifice after III.)
I — Create a 1/1 blue Bird creature token with flying. You gain 2 life.
II — Whenever one or more creatures you control with flying deal combat damage to a player this turn, look at that player's hand and draw a card.
III — You may put a card you own from outside the game on top of your library.

The forest grew fangs. The sky spread its wings.

Fable of Wolf and Owl

Whenever you play a green spell, you may put a 2/2 green Wolf creature token into play.
Whenever you play a blue spell, you may put a 1/1 blue Bird creature token with flying into play.

Whenever you cast a green spell, you may create a 2/2 green Wolf creature token.
Whenever you cast a blue spell, you may create a 1/1 blue Bird creature token with flying.

"Birds reach all parts of the world," said Barrin. "They will make excellent scouts."

Ordered Migration

Put a 1/1 blue Bird creature token with flying into play for each basic land type among lands you control.

Domain — Create a 1/1 blue Bird creature token with flying for each basic land type among lands you control.