User blog comment:FairyRaven/Fairy Tail Chapter 319: The White Knight, Review and Commentary/@comment-5201441-20130215172919/@comment-5668006-20130215174256

Mr. Wayne, I was like that's Obrah to! Then nope, just Frosch =(

I definitely think the shadow is what the strange magic came from because Jellal felt it when it first appeared!

He said it felt like Zeref's magic so maybe the shadow is part of Zeref? I don't think it makes sense though since Zeref is trying to to hurt people anymore or at least that's what he said 7 years ago.