The recent release of "Fairy Tail" chapter 504 confirmed the much-anticipated theory that Natsu has transformed into E.N.D. When Gray and Natsu went face to face, Gray asked him if it is true that he has transformed into E.N.D., to which, Natsu confirmed.

Gray recalled what Invel told him prior to his defeat. He said that the Book of Zeref has demons which Zeref created himself. It was revealed that the when Zeref realized the disadvantages of being immortal, he created these demons with the sole purpose of ending immortality. E.N.D. was the strongest of them all. He is so strong that he can even kill his immortal creator, Zeref.

Natsu Dragneel went on ranting about how he will kill Zeref but Gray refuses to hear more of it and suddenly lunged an attack.

"Fairy Tail" Chapter 505 Spoilers

Fans theorized that E.N.D. will not fight Gray because he still had some of Natsu's memory left in him. However, since Gray is blocking his path in killing Zeref, a battle between the two is still expected.

Juvia and Lucy will try to stop the two from battling but to no avail. It has also been said that Gray and Natsu will be interrupted by Zeref mid battle and hit Gray with his fire, which prompts him to retaliate. Will E.N.D. succeed in carrying out his purpose of killing his creator, Zeref?

On the other hand, it seems like the long overdue battle between Eileen and Mavis will finally happen. Eileen will use her illusion magic and will make a giant version of herself which Mavis will have a difficulty dealing with. Due to Eileen's immense strength, the rest of the Fairy Tail Guild will help Mavis win the fight.

It looks like a lot of epic battle will happen on "Fairy Tail" Chapter 505. Find out who will win when the next chapter comes out next week.