User blog comment:Stone Roger/Natsu and Zeref have somekind of relation?/@comment-4438931-20111015121638

My (ridiculous) theory is this: Dragon Slayers are over a hundred years old (remember when Natsu and Gajeel couldn't get past Freed's law that says only those below 80 years old could pass through?), and they must have defeated Zeref at some point in the past. They could have been brought to the present Fairy Tail time by a magic of some sort, which would justify the 80-year-old-law. I don't know.. I'm just as clueless as you are. xD