User blog comment:IamJakuhoRaikoben/Chapter 234: The Boy Who Stares At The Sea, Review./@comment-3290324-20110518034402/@comment-3545258-20110518040649

There's been a lot of speculation that Zeref is a Dragon Slayer, and that he met Natsu at some point in time when Igneel was his foster father. I'm leaning towards it, but since it's speculation, I don't fully believe it. And if that pic really is Zeref, maybe he had some history/trauma that led to his current reputation?