Quote Originally Posted by Alberel View Post
That was Lahabrea. It would seem his machination in having Ysayle merge with Shiva was an experiment for something he wanted to try himself. The voice of whatever is merging with him sounds a lot like Hydaelyn but immediately before that scene the camera conspicuously focuses on a statue of Halone so I'm more inclined to believe it's her.
Someone threw forward the idea that it could be corrupted Minfilia. I do quite like that one.