well, i thought about everthing for a little while... and still my brain got nuts. but i made a theory...
first off: we got natsu and gajeel and wendy trained by theire dragons. all of them dissapeared on the same date: 7, 7 777.
but what i was allways woundering, why does mashima sensei make such a big secret about the age of natsu and gajeel. i mean, it shouldnt be that big deal or? but then... here is the point.
both, gajeel and natsus dragon dissapeared on the same day... makarove found natsu in the forest (about gajeel we dont know till now). he entered ft during his childhood. so basicly he should be at the age of 16- 17 by now. but in the lFT Battle arc he couldnt escape the barrier from fried. so how old is he really? my personal guess is about the "younger 400" years old. basicly.... natsu was born back in the year 370 or so. we already know a spell that keeps you in a frozen state where you dont age, fairy sphere; what would also connect the whole dragon thing more to ft and deeper to ft roots. natsu used to live only with his dragon in the forest as we know, so it mustnt nessasarly mean that he really know about the date where he was with his dragon parent. so by any mean... anything happend in the year on 7, 7 377 where igneel didnt saw any other way to save him as to keep him in a frozen state. everything he left for him was the muffler and natsu awakens in the year 7,7 777 and his dragon was suddenly dissapeared. if igneel casted that spell on him while he was at sleep, natsu wouldnt notice at all (same as fairy sphere). and so 400 years passed without even noticing it (by natsu).
the same thing could be the case with sting and rouge just in a diffrent way. lector was friends with him since he was a kid. vicelogia and skydrum could have made a similar move to theire dragon slayer, but they let it look like sting and rouge actual killed them.
then we got wendy, she is 12 years old and grandine dissapeared 7,7 777. so we could guess that grandine was still arround. since she was saved by mistgun back in these days, the only thing we can say is that grandine was arround for that time.
now its going to be a bit complicated;
now comes our lovely zeref; what part does he play in that thing? arcadios said that he is immortal. so he could lived for this 400 years without any problems. the fact that he knows natsu, but natsu doesnt seem to know him was mokking me. so i thought, how about that: could it be that zeref was friends with the human- liking - dragons? it could really be that it was zeref itself who put natsu asleep. zeref allways used to speak about natsu in a.... lovely way? like he was a little brother to him? in the year 377 on july the 7th something terrible was about to happen, and igneel asked zeref to safe natsu? and zeref took care of him for the time natsu was asleep?
that also could explain why zeref knows him, but natsu not him. so... now another guess. when it was zeref who transformed the person into acnologia. maybe that happend in the time 400 years ago. he recognized that he did something terrible and wanted to stand up for his crimes and decided to help the dragons fighting accnologia. in the end they couldnt make it and had to escape. they started to train theire dragon slayers (natsu, gajeel) and acnologia was affraid of the power. so he went after them. maybe something like that happend on july 7th in the year 377. igneel didnt saw any other way to save his "child" as to ask zeref for help.
zeref saved natsu, the dragon dissapeared to somewhere. as we know zeref is close to the source of magic. maybe he invented the god slayers by himself by teaching them dragon slayer like art of fighting with the source of magic. would also explain why jellal feeled the same kind of magic when shelia was fighting. he did that on purpose to fight against acnologia the time beeing, while the young dragon slayer were asleep. accourding to my threat, that would have happend in the 7-9 years after 377. so natsu woked up in the age of 7 or something like that while zeref was still sleeping...
zeref must have figured that acnologia is able to sense his magic, so he didnt saw any other way to protect them as to lay himself asleep in his own body and on tenroujima iland that seal on himself broke too and acnologia could sense him again and attacked the iland. would also explain the expression on zeref at this page:
http://www.mangapanda.com/fairy-tail/253/17
also why he was so god damn angry at grimoure heart, since they tried to breake that sleeping seal to awake him. he said, they would pay for the crimes... well its just matches so hard.
ahhh, even while im trying to explain that, my brain gets more and more nuts.....
