User blog comment:Natsu11/Zeref and Natsu?/@comment-1595565-20140214071933

You are making a lot of assumptions with very little to go on. The scarf was more than likely endowed by Igneel with some kind of magic. Since it was magic used by a dragon, it would only make sense to say that it was dragon magic. If only dragon slayer magic can destroy a dragon, then other magic wouldn't work in damaging the scarf. However, Zeref's magic is still powerful enough to have some kind of effect, albeit minor. So if he were indeed a dragon slayer, the scarf would have been destroyed. Major hole in your idea right there. Natsu is not 400 years old. I know this because he ages normally. If he were 400 at his current rate of growth, he should look old enough to make Porlyusica or Ultear look like Wendy.