第 50 集: 妖精尾巴封印龍王，阿克諾羅基亞的過去揭曉
Four-hundred years prior, the human Acnologia learns Dragon Slayer magic to take revenge against all dragons for his home's destruction. Forgetting his original name, he renames himself Acnologia after his former guardian as a symbol of his hatred, eventually transforming into a dragon. In the present, Gray and Lyon create a new ship made of ice, while Erza forces Acnologia's body onto it with her weaponry. Lucy uses all of Fairy Tail's magic to cast Fairy Sphere on Acnologia while he is afflicted, but their power is insufficient. As Acnologia begins to break free, Meldy uses her Maguilty Sense to reinforce the guild's magic with those of the wizards across Ishgar, which successfully contains Acnologia. Meanwhile, Acnologia's spirit defeats all of the Dragon Slayers except for Natsu, whom Wendy enchants with all of their magic in a final effort to overpower Acnologia. (Source: Wikipedia)