User blog comment:IamJakuhoRaikoben/Chapter 370: Demons Reincarnated, Review./@comment-1359064-20140207151624/@comment-1359322-20140207153216

It's more like Prologue is to show the fans about Tartarus and their purpose. Part 1 is to show Tartarus' attempt to unsealed Face, which they have succeeded. And now Part 2 is for Tartarus to try and activate Face. Could be some other reasons, but who cares.