Key of the Starry Sky arc

The Key of the Starry Sky arc is an anime-exclusive story arc of the Fairy Tail series. The arc happens between the X791 arc and the Grand Magic Games arc. When Lucy's cousin, Michelle, arrives at the Fairy Tail Guild to give Lucy a memento left to her by her father, Lucy and her friends go on a quest to unveil the mysteries surrounding an ancient device sealed away for centuries, the Infinity Clock. However, with the involvement of the Legion Corps and the newly restored Dark Guild, the Reborn Oración Seis, the fate of the world as it is known is left to none other than Fairy Tail to protect. An old man wakes up from a dream of a church engulfed in flames and a mechanical bear uttering ominous words. An unknown girl is later seen on a train with a case in her possession. At the Magic Council Headquarters, Lahar and Gran Doma discuss about several cases of churches being destroyed and Lahar is tasked with finding and arresting the culprit. In the Fairy Tail guild hall, Lucy reads the news about the church bombings. Suddenly, Romeo announces that Lucy has a visitor, pointing Lucy out to the girl who was on the train earlier.

When Lucy asks the girl to identify herself, she tearfully introduces herself as Michelle Lobster, revealing that she's Lucy's younger sister, stating that the Heartfilia family and the Lobster family are distantly related. When the others comment that she seems older, they theorize that this contradiction arises due to the events on Tenrou Island. When Lucy inquires as to the contents of the case the other girl carries, Michelle says that the case contains a memento from Lucy's father, as the girl had known him and was even present when he passed away. Lucy opens the case and finds an object wrapped in bandages, which she unwraps to reveal a strange mechanical gear. Natsu smells a spell on it; however Carla appears terrified upon seeing the wrapped item. Lucy and Michelle later walk to Lucy's Apartment, where they decide that Michelle should live with her. Lucy later writes a letter to her mother about Michelle working at Fairy Tail as well as living with her. Some time after this, back at the Fairy Tail guild building, Natsu tells Lucy that they're going on a job to catch some bandits. Despite Lucy's warnings about the dangerous nature of such jobs, Michelle insists on accompanying them, claiming to want to see what it's like to be a Mage. After some encouragement from the others, Lucy aquiesces. Later, on a ledge overlooking a path through a forest, Erza explains her plan to capture the bandits. When Natsu rejects the plan due to the involvement of transportation, Michelle decides to play an active role rather than being just an observer. Though the others are a little hesitant, they eventually agree. The Mages soon put Erza's plan into action, with Michelle taking the reins of the wagon and leading the cart into the bandits' territory. After Lucy fails to seduce the bandits, Team Natsu attacks, quickly defeating them, with Michelle completely dazzled with the group's strength. Meanwhile, back at the guild, as Wakaba and Macao talk about Michelle, Laki arrives and reads the report about Michelle's family to Macao, Carla and Wakaba. Meanwhile Lahar investigates a recently destroyed church, and finds many things about the incident mystifying. Michelle suggests officially requesting the guild to solve the mystery behind the memento, which Lucy agrees to. Whilst Natsu and Lucy discuss the job and Carla still appears distraught by the memento, Michelle accidentally drops the gear, and it starts levitating with runes appearing on it, but since Levy and Freed are not present, no one is able to read them.

When they turn to Makarov for help, he tells Lucy not to get involved, but Lucy states that she wants to solve the riddle her father has left her. While Michelle and Lucy are looking through some ancient rune books to decipher what is written on the metal rod, Erza and Gray arrive at the guild to inform Lucy that they will be going off on a job to retrieve stolen gold, but Lucy refuses, stating that she's busy. Realizing that Natsu has gone off somewhere, Erza tells Gray that just the two of them will complete the job, which makes Juvia incredibly jealous and angry. In the forest, Laxus pulverizes an aggressive Gorian, with Natsu, Gajeel and the Thunder God Tribe noticing Laxus' lightning and converging where he is. On the way, Natsu bumps into Gajeel and both make clear their intention to have a one-on-one duel with Laxus. Upon finding him, Natsu directly challenges Laxus, with Gajeel following suit. When the Thunder God Tribe jumps to Laxus’ aid, Laxus states that he will defeat Gajeel and Natsu with his own fists, choosing to fight Natsu first. As the two prepare to battle, Wendy arrives and stops them, telling them that it would be better to plan the event first and for the battle to take place the next day instead. Everybody agrees and it is decided that the showdown would take place at the Sola Tree in South Gate Park, with Gajeel's battle after Natsu's. Meanwhile, at the guild, Macao, Wakaba, Mirajane, Elfman, Lisanna, Romeo and Kinana discuss about the upcoming duel. Elfman suddenly suggests holding a festival in honor of the showdown and they all agree. At the festival on the night before the battle, Jason appears as the commentator for the event, while Natsu and Gajeel enjoy themselves instead of training. Lucy meets up with Levy, who has returned recently, and asks her to help her decipher the writing on the iron rod. Meanwhile, somewhere in the mountains, Gray and Erza have located the bandits' hideout but unbeknownst to them, Juvia has followed them. Gray and Erza try to get some sleep, but soon after, the bandits return, with Gray and Erza attempting to stop them. However, the bandits have hired the Vanish Brothers to defend them, which leads Gray to request that he be allowed to defeat them alone, since Natsu was able to defeat them unaided seven years prior. For a while it seems that Gray is about to be defeated, but ultimately he defeats them, taking back their client's gold along with Erza and heading home. Meanwhile, the Thunder God Tribe and Laxus arrive at the festival, while, in the forest, Wendy and Carla meet Makarov and inform him about the showdown, shocking him. As the fight begins and the crowd watches them tensely, Natsu makes the first move, to be ignominiously knocked out in one hit. As mirth and shock travel through the crowd, Laxus turns to fight Gajeel, only to find out that he has fled, with a search party immediately setting out to find him. As Makarov arrives at the aftermath, Freed pleads with him to take Laxus back, but both men involved remain silent. At Lucy's house, Levy manages to decipher the writing on the mechanical rod, informing them that the script is ancient Potamelian and reads "Time is etched and then chaos descends". Lucy suddenly remembers the phrase, retrieving a book from her shelf, and reading out a story about the strange destiny of a clock that had been passed on for centuries. They then find out that the rod is actually the hand of a large pendulum clock. Back at the guild, with just the 3 Exceed occupying it, three mysterious people approach the building.