User blog comment:Nerdyanimegirl225/Best Villain, Worst Hero./@comment-31.132.65.60-20140612103736/@comment-7418318-20140612151732

I don't think Zeref called him. He even said that Acnologia was attracted by Hades and his people's misdeads.

Not that I take that literally, or Acnologia would have to turn up quite often whenever Humans do bad stuff. Maybe aquiring the so called "Keys to Zeref's awakening" were what caught Acnologia's attention.