Lullaby arc

The Lullaby arc is the third story arc of Fairy Tail. This arc includes the first appearance of Erza Scarlet, as well as hers and Gray Fullbuster's first actions as main characters. The story follows Team Natsu as they attempt to stop a Dark Guild, Eisenwald, from using the Lullaby to assassinate the Guild Masters. Lucy begins to search for her next job but has a hard time on deciding which one. Mirajane tells her that she contact her if she finds one she wants due to the Master being off at the annual Guild Master meeting. She then explains to Lucy about the structure of the Magic World government and how the peace is maintained. She also informs her about the Dark Guilds which don't follow the rules of the council. Shortly after, Natsu and Gray begin their usual bickering while Loke flirts and tries to ask Lucy to form a team with him. However, Loke notices Lucy's Celestial Spirit Keys and quickly runs away from her in panic. Nevertheless, he arrives moments later to tell the guild about Erza Scarlet's return, much to everyone's shock. Erza then walks in the guild, carrying a giant monster horn and soon starts to scold everyone for their bad habits as well as the trouble they have caused.

She later asks where are Natsu and Gray and Lucy is surprised to see them afraid of Erza. Mirajane explains how Erza could easily beat up anyone, like Natsu, Gray and Loke, to a pulp, making her a fearsome Mage. Erza then asks Natsu and Gray to form a team with her and help her on her next mission. Due to such act, Mirajane comments that they could be Fairy Tail's strongest team ever. The next day, everyone arrives at Magnolia Station, waiting for the train's departure. Once there, Natsu and Gray continue their argument while Lucy, asked to watch the two, tags along. Erza then arrives pulling a cart full of luggage bags. Before they leave, Natsu tells Erza that he will come only if they have a match upon return. Erza accepts Natsu's challenge and so the team gets on the train. On the train, Natsu gets motion sick so Erza decides to knock him unconscious to make him feel better. After some small talk about Magic, Erza proceeds to explain their mission, having grown suspicious after overhearing some men in a bar talking about a sealed Magic Item called Lullaby. Erza adds that she initially thought they were Mages on an unsealing job, but that thought was erased when she heard the name Erigor, the Shinigami of the Dark Guild Eisenwald, who only takes on assassination requests. She then reveals that she plans to head straight to the guild with them. Upon getting off at the next station, they quickly realize they left Natsu on the train which has just departed without them. Natsu, still sick, gets an unexpected visit from Kageyama, a member of Eisenwald. After Kageyama lightly chats with him, he suddenly kicks Natsu in the face so they begin to fight. Natsu has trouble at first since the train keeps moving. However, the train suddenly stops, thanks to Erza and the others who hit the emergency brake for his sake. Due to the sudden halt, Kageyama drops a strange flute which Natsu catches a glimpse of. Angry Natsu then hits Kageyama in the face with Fire Dragon's Iron Fist. When the train starts to move again, Natsu jumps out of the train window and bumps into Gray, who is at the top of the Magic Four-Wheeler Erza is driving in order to catch up to the train. He tells everyone about the Eisenwald member who attacked him, resulting in him getting a slap in the face from Erza for not stopping the Eisenwald member, even though he was unconscious when Erza told them about Eisenwald.

When Natsu mentions the flute he saw, Lucy quickly realizes what it is and reveals the mysterious flute to be Lullaby, capable of producing an enchanted, genocidal song that sucks out the souls of anyone who hears its tune. Meanwhile, Kageyama meets up with Erigor at Kunugi Station and gives him the flute. Erza and the gang try to chase after them before they can use the Lullaby. Erigor later gets furious with Kageyama for having someone else see the flute so he cuts a bit of his ears with his scythe as a punishment. Meanwhile, Team Natsu is still searching for Eisenwald. Happy tries to remember something he had to do something that relates to Lucy. After a while of Erza's speedy driving, they get to the Oshibana Station, only to see the damage done to it. As they rush in, they find the army pulverized by Eisenwald. They soon meet the entire Eisenwald Guild in the innermost parts of the station. Erza asks what Erigor is planning to do, with the latter replying that he plans to use the broadcasting system of the station to play the Lullaby's melody throughout the town. Erigor claims that those people who will die are simply being punished for their sin of not knowing that there are those who have been revoked of the rights they revel in. After hearing Kageyama's voice, Natsu manages to recover and ends up saving Lucy from Kageyama's attack. As Erigor flies away, he leaves the rest of Eisenwald to fight Team Natsu. With her staying to fight, Erza orders Natsu and Gray to chase after Erigor. They quickly comply while Rayule and Kageyama follow the two.