The previous chapter of the popular manga "Fairy Tail" revealed that Juvia had survived her suicide attempt but at this point Gray is still unaware of her condition and had battled Invel out of sheer rage. As stated in a report from Yibada, Gray's battle are not yet done as he will be facing Etherious Natsu Dragneel (END) in chapter 501.
It has been revealed that END is the real enemy that Gray has been looking for all this time and it is expected that he will be fighting END throughout the next chapter. According to the report, series creator Hiro Mashima had indicated there will be a major death before the series ends and it could be Gray's.
Fans of the series who have read the original release of the series and its anime adaptation will recall that Natsu is in fact the END that was created when the main antagonist Zeref reincarnated his younger brother as a means of preventing his immortality from coming to an end and this will conflict with Gray's personal mission.
When Gray learns of Natsu's true nature it is expected he will hesitate to kill Natsu given that they have been travelling together for so long.
My Manga Marathon also reveals that chapter 501, titled "Mari and Randy," will explore the two character's backstory. This is also the manga where Lucy and Natsu finally meet Zeref and the latter will reportedly mistake Lucy for Anna or Layla, hinting at the mysteries of her character.
Eileen and Erza are also stated to head against each other in a battle but according to the reports it is hinted that the former is Erza's sister or mother and the revelation of this truth will also take place in "Fairy Tail" chapter 501. How this will further affect Gray and Natsu's story has yet to be revealed.
"Fairy Tail" chapter 501 is set to be released on Sept. 12.
