User blog comment:FairyRaven/Fairy Tail Chapter 416: Tartarus Arc: Final Part, Review and Commentary/@comment-162.207.38.121-20150120001811/@comment-9595671-20150120214558

I wasn't trying to do that before anyone says anything, but I think we can agree that Fairy Tail's art has improved a lot.

The only other manga that I remember having its art evolve while it was being made is My Bride's a Mermaid.