User blog comment:FairyRaven/Fairy Tail Chapter 470: Hybrid Theory, Review and Commentary/@comment-25111584-20160125131040/@comment-9595671-20160126184944

It's confusing since Zeref's plans took 400 years and had time travel involved, while Mavis' are more recent being around the last 100 years and being a spirit who died when she was undying. It's hard to keep up.