Quote Originally Posted by MercuryD View Post
Well as far as the fight is concerned, it always seemed like post diamond dust was the real Shiva in place of Ysayle.
I honestly think it unlikely we saw anything of the 'real' Shiva beyond her physical form. It was made pretty clear that the Echo allowed Ysayle to remain in complete control the whole time. For the 'real' Shiva to take control Ysayle would have to be tempered, which she is immune to just like the WoL. Anything said during that fight should have been Ysayle speaking based on what we understand of channeling a primal into your own body. It's for this same reason that Summoners can safely channel Bahamut into their own body in Heavensward.