The Second Incarnation was created when the First Universe ended. At the end of ever previous Incarnation, the Fragments of Magic gather of millions of years and form the new Origin of Magic, then the Origin reanimates Màgya and channels within her all of its magic and then she self-explodes and creates the new Incarnation.
What is known about this Incarnation is that instead of Magic they call it chakra, instead of spell they call it jutsu, they use hand signs in order to activate these jutsus and they are called Nages or Ninja Mages. The common thing about the 14th and 2nd Incarnations is that they both use their eyes as their door to their magic roots within their soul. Feria awakened easily by thinking of all of her pain the Rinnemagic, according to the Elder of that Incarnation, that eye is the most powerful eye of said Incarnation. When Feria traveled to this Incarnation, she found out that the older a spell gets the more powerful it becomes. she came looking for the original reanimation spell where here it is called "Edo Tensei". Normally when an Incarnation ends, it ends for good but after Luna's spell, all Incarnations coexist. After it normally ended, Celestia absorbed all of its magic and became its Darkness manifestation.