Natsu Dragneel... Think about it. E.N.D. Natsu Dragneel is N.D. Hehe. What if Natsu is END? And END stands for Evil Natsu Dragneel (sounds corny but possible). Maybe that explains why Igneel couldn't kill him? And why Zeref mentioned that "You or E.N.D. will be able to meet me... Life or Death?". Makes sense right?
Gray on the other hand... Bothers me. Silver might be his future self (just like Lucy and Levy). Besides... Silver and Gray are both color names lol. Thought of them first as father and son but Future counterparts are more possible.
Thoughts about this anyone? :)11:53,4/10/2014