Astral Eggs are the products of stars. Every star will spawn at least one in it's "lifetime." A star will flare and release a mass of stardust. The stardust will slowly compress itself into a sphere, and then harden. The newly formed egg will fly through space in a straight path until it finds an object to land on. The egg will remain there until an animal (or similar creature) touches it. It will then glow and take the shape of that creature, as well as copying their anatomy and abilities. The newly born being will be like a baby, and know nothing except the star from which it came.
The only known Astral Beasts on Earth are Rigel and Aldebaran. Rigel was born from a pancham, and Aldebaran was later born from Rigel touching his egg. For reasons unknown, Aldebaran became evil and his fur was not the proper colour. Astral Beasts are full of their star's energy, which grants them a wide variety of powers, but little knowlege of how to use them. They are able to rearange their physical forms and transform into anything they've seen before, even in a picture, and gain the abilities of what they've transformed into. They can also shoot blasts of energy (colour depending on the colour of their star) and can use the energy to charge other objects. They can power themselves up, too. With enough skill, they can run at great speeds, fly, and turn their entire bodies into energy. Astral Beasts have incredibly long lifespans and are durable creatures. They are hard to kill, though it is possible. Astral Beast is an umbrella term for all creatures born from Astral Eggs. The proper name for a specific Astral Beast is Astral, followed by the species the beast was born as. For example, Rigel is a Astral Pancham, and Aldebaran is a Astral Pancham-C. The C is added because his egg hatched when another Stellar Beast, Rigel, touched his egg, so he is, in a way, a clone.