Magatama. 8 maidens? Or 8 cycles have passed. (Yoshiro is the 8th Maiden!)
The Sword.
The mirror. (Behind her)
Could it be that she looks like Soh and Yoshiro because she is the 'mirror'? And the mirror is Amaterasu's symbol. But why does she look like this? Why this specific design?
It looks like she mirrors Yoshiro's defiled state and Soh's abilities and outfit + Yoshiro's hair. But why reflect this combo?
I think we are witnessing the birth of Amaterasu in the Kunitsu-Gami universe.
Soh is associated with mirrors from the very beginning of the game and for the rest of it, because of her attacks reflecting a kaleidoscope and her using a mirror to move onto the next cycle.
If Soh is a former shrine maiden, then she can represent the magatama, the sword and the mirror?
When they say 'the mountain gives birth to the rising sun', could it be that Soh became the god Amaterasu? (Is the forgotten goddess...Soh?)
In a previous post, I wrote: When Yoshiro becomes a home for the Goddess and then absorbs defilement, this might affect the goddess herself? Is this what Cursed Soh is?
Soh defeats the Cursed Goddess...and absorbs her power? Because Soh is a fraction of the goddess, untainted, and was able to absorb the power, becoming even greater?
Yoshiro has a magatama embedded on her chest. It's not attached to the necklace. Isn't there a story about Amaterasu creating children by breaking up a necklace with her mouth and spitting out magatama that became her children?
Yoshiro is also said to have descended from heaven alongside Soh. I wonder if the maidens are 'daughters' of Amaterasu. Perhaps Amaterasu split herself up and then is finally put together at the end?
And that's what the 8 symbols are?
But the 'becoming a god after 7 generations' is more likely because Yoshiro does not get sacrificed. (Except in NG...did Soh rewind time?)
Unless we have 8 in the symbol, because we did have 8 maidens, but 7 passed which birthed a god.
(Crab posted this image on his theory page and I had to put it over the symbol. His theory has been updated, as I've mentioned before!)