The upcoming chapter 506 of "Fairy Tail" may feature an unlikely alliance, in order to achieve a greater good as it is said that Natsu and Gray may halt their battle first to join forces and defeat a bigger enemy to both of them.

It can be recalled that in the previous chapter 505 of "Fairy Tail," despite already winning, the Fairy Guild started losing after Eileen cast a spell that made the Alvarez army stronger and enabled them to defeat the guild. After seeing that the fairies were losing one by one, Makarov cast a powerful spell called the Fairy Law, which, unfortunately, resulted in his demise. Hence, it is suspected that the upcoming chapter of the manga series will feature the remaining members of the guild avenging the death of their guild leader.

According to other sources, "Fairy Tail" chapter 506 will cast the spotlight on Mavis as she confronts Irene. While Natsu is supposed to help Mavis, it is said that the latter could not wait for the former to return, hence, she leads the guild to the battle.

However, more than the fairy mages avenging the death of Makarov, it is also alleged that the upcoming chapter 506 of "Fairy Tail" will have Gray and Natsu finally teaming up. With the unlikely team-up of the two, it is expected that Zeref and the Spriggan 12 will finally be defeated.

To the uninitiated, Natsu is the reincarnation of his dead brother and has been prophesized to be E.N.D. (Ethereal Natsu Dragneel) whose mission is to destroy Zeref's immortality. As Gray was affected by the attack of Etherious Deliora when he was just a kid, and he inherited the role of being the demon slayer, the revelation that Natsu and E.N.D. are one and the same fell on his bad graces. However, no matter how hard Gray tries, it is said that he'll never defeat Natsu at all as the latter was created for the sole purpose of destroying Zeref, which means he is more powerful.

Will Natsu and Gray really team up against Zeref? Will they succeed in ending him? Find out when "Fairy Tail" chapter 506 hits the shelves tomorrow, Oct. 18.