Natsu Dragneel & Lucy Heartfilia vs. Jacob Lessio

Natsu Dragneel & Lucy Heartfilia vs. Jacob Lessio is a fight fought between Fairy Tail Mages Natsu Dragneel and Lucy Heartfilia, and Jacob Lessio of the Spriggan 12.

Prologue
As Lucy and Happy continue to watch over a sickbed Natsu, up above in the guildhall, Warren reports the fall of Dimaria which in turn lowers the count of active Spriggan 12 members to seven. The guild celebrates, however, Mavis voices her concerns over the two unmoving markers to the east, and as she does so, the Shield of Spriggan Jacob Lessio arrives at the guild, where he comments on the wonderful scent of the "charming" building. When asked who he is, the man introduces himself as a member of the Spriggan 12, which takes them all by surprise. When Warren and Makarov check the markers to the east on the Magic Radar, Jacob reveals that the elderly Mage August, also apart of the Spriggan 12, learned they were being tracked and camouflaged their real positions. Cana mentions that it takes courage to barge into the guild alone, but Jacob simply replies that he has no soldiers, which allows him to do as he wishes. The man then goes on to warn the guild about August, citing that he has no sense of humor, and that he went ahead of him as a gesture for Alakitasia's Respect for the Aged Day, which happens to be the day that they are on. Jacob goes on to demand alcohol, but Makarov vehemently refuses to serve him any, which Jacob remarks is a shame, as he was trying to show the elderly Makarov some respect for the Alakitasian holiday. The Spriggan then goes on to explain to the guild that he is a master assassin, never failing a single assignment; when asked by Max why an assassin would walk brazenly into enemy territory, Jacob replies that he has no reason to hide, as the only thing he'll be hiding are the corspes and witnesses, which the assassin goes on to erase all the traces of everyone in the guild after clapping his hands together, leaving Mavis' ethereal body as the only one unaffected.

Mavis, shaken from the Spriggan's power, begins to call out the members but it is to no avail. Much to her surprise, Jacob notices her and quickly deduces that she is Fairy Heart; able to attack her, Jacob begins to gravely torture her, which unknowingly damages Fairy Heart below, offering her incapacitated but still alive friends as collateral for the location of the Eternal Magic. Before Mavis is forced to make an impossible ultimatum, Lucy arrives in her Taurus Star Dress, kicking Jacob away from behind. Jacob wonders how Lucy and the quickly following Happy escaped his Magic, causing Lucy to think back to five minutes earlier, when Horologium saved her, Happy and Natsu from Jacob's assault; something she responds to by saying the stars blessed her. Jacob smirks, proceeding to antagonize Lucy, while changing the ransom from Mavis' whole guild to Lucy's life, threatening to mutilate her should she not comply with his demands. The man then throws a knife at Lucy, but Natsu, who is now fully healed, intercepts and melts the weapon, threatening to turn Spriggan 12 into ash after regarding that Lucy would always be the same regardless. With his three remaining guildmates overjoyed at his return, Natsu responds to Lucy's question about his "nap" by saying that he enjoyed it, and that he's been completely rejuvenated for the bout.

Battle
Their battle begins as Natsu charges to engage Jacob, as Lucy, Mavis and Happy are glad he's back up and moving. Natsu goes in to kick him but it is parried by the assassin, who uses Natsu's signature catchphrase to state his glee in the bout, annoying the Dragon Slayer. Jacob quickly knocks back Natsu but the latter bounces off a supporting beam to charge straight for the Shield of Spriggan and nailing him with a chest blow. The assassin goes in to grab around his neck, powerfully slamming the Mage into the ground before disappeaing in thin air, which causes wonderment from him. He quickly reappear behind him to hammer him and once again disappears, which Mavis opinions this Magic is Stealth, which can make the user completely camouflaged in the background. Jacob reappears with his foot on top of Mavis' head, going on to explain his Magic on how it is also able to see the unseen, such as her ethereal body. Lucy realises that he hasn't completely disappeared, only vanished, summoning Loke to illuminate the room, which the Celestial Spirit goes into attacking the assassin, only to get knocked back, amazed at his power. Jacob then unleshes multiple invisible projectiles at the Mages, cutting and slicing them up, while then going on to use a invisible whip to batter Lucy from behind.

He soon reappears behind Natsu and pins him down, declaring he will show him hell on Earth itself, directing his eyes toward Lucy, whose clothes begin to vanish, stunning the latter as she is only trotted down in her underwear. Natsu unphased by this, stating that he always she the girl in this type of attire, which causes the assassin to be flustered; Lucy noticing his face has been contorted by the sight of her indecency due him not wanting to see it, goes along with Natsu's plan to make curious sounds and movements to continue to fluster the Spriggan 12, who finally has enough and undoes his Magic. Taking advantage of the scenerio, the two Fairy Tail Mages knock back the assassin with their own kick, this whole event of their fight garners Mavis' attention. As the Shield of Spriggan begins to go in a fit of rage, Mavis quietly observes the scene before coming to an epiphany on how to finally take down the immortal Zeref.

At guild hall, Natsu and Lucy are still fighting with Jacob Lessio who manages to overwhelm the two with hand to hand combat and his Magic. After knocking the Mages away, Jacob resolves to kill their guildmates who still has trapped. Natsu dares him to try while Mavis screams against this act but Jacob is too annoyed with the young Mages to listen to reason. However, Lucy gets an idea and points out to Jacob that one his allies, Brandish, is trapped as which shocks Jacob who quickly checks to confirm and finds that not only Brandish but her servant Marin are trapped. He immediately releases them as Brandish and Marin express surprise at seeing Jacob. Marin thanks Jacob but is greatly shocked to see another version of himself greeting him, everyone in the Guild soon learns that Lucy had summoned Gemini in her Star Dress and had them turn into Marin. The transformed Gemini then proceed to use Marin's Rules of the Area which cancels out Jacob's Transport, thus bringing back everyone to the guild.

Once everyone returns they congratulate Lucy on her quick thinking, while an infuriated Jacob tries to use Magic to make them vanish again only for his attempt to be stopped by Happy. An angry Makarov approaches Jacob furious at him for hurting Mavis, recalls Jacob had previously stated it was "Respect for the Aged Day" stating if that was the case the latter should of showed Mavis more respect than anyone before using his Giant to punch Jacob out the Guild. Natsu tells Makarov to not destroy anymore of the guild until the latter grabs him and throws him after the Shield of Spriggan. Using the air projection from Makarov's strength, Natsu activates his Fire Dragon King Mode with the intense heat burning Jacob before Natsu strikes him with a powerful punch defeating him, as his guildmates cheer him on.

Aftermath
After their bout, Brandish willingly returns to cell where she is greeted by an exuberant Natsu, as well as Lucy and Happy; the Dragon Slayer thanking her for saving his life. She shuns him, muttering under her breath that Jacob was defeated but says it doesn't matter, as she proclaims of the impeding reality that her comrade, August, is on his way to the guild, stating that the war is all but over. Outside, the members begin repairing the side of the guild in which Makarov destroyed; with Warren's Magic Radar still on the fritz, they cannot identify the incoming threats of the the Spriggan 12. Makarov lets them know that he's weary of the feat of the elderly August, who is currently on their way, that he is someone that shouldn't be taken lightly. Underneath the guild, Mavis and Cana are visiting the location of Fairy Heart; Mavis explaining to the latter that she has thought of a plan to defeat Zeref, but needs Cana to destroy her current Thought Projection using Fairy Glitter in order to free her real body currently inhabiting the Lacrima. Cana digresses, as she does not know of the consequences that could damage her body, but Mavis urges her she must as this is the only possible route.