Extraordinarily powerful supernatural entities created by the Aeva, forged in the same crucible of celestial creation as they were, are known as Astras. An Astra is usually created to live in service, or perform a particular task, their fate bound to the stars.

An Astra's fate can be bound within a soul, not unsimilar to how they are bound to the stars by the Gods. It is by this means that ancient heroes and kings wielded them as weapons. But, beware - An Astra will not likely willingly join with a mortal soul.