Board Thread:General Discussion/@comment-31283382-20140615231853/@comment-8986886-20140905035845

Will-O-Wisp wrote: An omake in the manga hints at "the Assimilation" being the most likely. Can't find the picture now, but it shows many letters attached to an A.

If so, then Yhwach's got something in common with the Borg. "Resistance is futile..."