User blog comment:Mamerge/What if Natsu is END? And Silver is Future Gray?/@comment-24784846-20140506000006

Well that sounds logically seeing Igneel failed to kill END. Also I don't think Silver is future Gray, and the reason being so is because Silver was turned Etherious by Zeref 400 years ago and this is stated that all all of the 9 gates are demon from Zeref's book, so Silver existed 400 years ago, perhaps Silver is a version(not sure which one) of Gray that went to the past with Team Natsu and got stuck in the past, later Zeref found him.. I will laugh if this turns out true