Eggs

Eggs are a resource allowing you to hatch new birds.

Procurement

 * You receive free hatches every day.
 * However, the most effective way to obtain eggs is to complete scouting random missions or advance the story. Depending on the location you fight in, you will acquire different kinds of eggs. For example, the desert produces only yellow eggs, while the blue forest generates only blue eggs. Fight accordingly.
 * All eggs gathered in the field, so to speak, are automatically hatched at the end of combat - if you survive, of course.