User blog comment:Sargenttacos115/Natsu and Gajeel age Theory/@comment-76.169.61.239-20140806234440

I heard one theory that sounded cool, where Natsu is one of Zeref's creations, which is why Zeref knows who Natsu is and why he thinks Natsu is the only person capable of killing him. I was thinking that after Zeref regained his care for humanity around 400 years ago (where he stopped killing and people thought he died or asleep), he decided he wanted to die and so created Natsu to kill him. However, in this state Zeref is also weakened and so Natsu was created as an infant incapable of killing Zeref. Some time after (before or after time travel), Igneel discovers Natsu and raises him.