User blog comment:FairyRaven/Fairy Tail Chapter 435 & 436: The Cry of Victory & Memoirs, Review and Commentary/@comment-24546844-20150519195052

I've ask this on BWZ's blog but I feel asking it here too won't do any bad and maybe i can get more opinions so:

People's been talking about Tartarus and how E.N.D. is supposed to be their master so I'll rise a question I've beeen thinking about for a while. If Natsu is E.N.D. and is Tartarus guild master, yet they never actually met them, and if Igneel trained Natsu some time before he was born and thus teaching him his fire magic, how could Silver know that E.N.D. is a fire demon? Could we assume Zeref revealed it to Tartarus some time before? Or did Silver somehow knew that E.N.D. was Natsu?