After Irene's death and the dispelling of Universe One, Natsu, Lucy, and Happy plan to go to Fairy Tail's guild hall. They meet up with Porlyusica, Evergreen, Carla, and an injured Juvia, who tell them that Gray has gone missing. Before Natsu and Lucy can react, the ground begins to shake by August, who stands on top of Kardia Cathedral. He mentions that he is the last of the Spriggan 12 standing as he prepares to destroy the whole town. However, Gildarts suddenly appears attacks August from above, August blocks his attack which destroys the whole cathedral. Gildarts then says that he will take on August. The two proceed to stare at each other.
Gildarts then throws away his cloak and charges at August in order to hit the Spriggan Leader, who dodges all of his punches. Gildarts then runs behind August and strikes him with Crush. This causes August's body to fall apart into cube-shaped objects, only for August to reform himself as he comments that Gildarts' Magic is interesting. As the Fairy Tail Mage is punched punches some distance away, he is shocked that his Magic has no effect on the old Mage.
August then uses Sink on Gildarts who, in return, uses Crush again to escape. Continuing his barrage of spells, the Spriggan affects his opponent with Rip, with the latter affected for a moment, but he manages to brush it off as he jumps towards August, but to no avail as Gildarts is sent flying through the air with Blast launched towards him. He then uses Crush again to destroy the ground, allowing him to land and charge at August once more, who blocks him and uses Realize, transforming himself into disassembled cubes. Reassembled, August appears behind Gildarts, allowing him to strike the Fairy Tail Mage and send him flying backwards.
After this showcase of Magic, August tells him that it is impossible for him to be defeated, just as Magic Cards are thrown at him by Cana, who arrives and tells him that her father can make the impossible possible. Gildarts tells Cana to stay away as August smiles as he realizes that they are a father and a daughter.
The battle is then interrupted when all three sense the arrival of Acnologia. August solemnly states that their time is now up and without Fairy Heart, the world is doomed. Gildarts tells August that he gives up too easily and that August and his forces are also on the same track to doom the world. August tells him that Zeref is acting in order to save humanity. This angers Cana who tells August that many people have died in the war, including Makarov Dreyar. Cana then decides to use Fairy Glitter on August. He, however, emerges uninjured from the attack, shocking Cana and Gildarts. August asks them if they love each other, and then tells them that he has acquired and mastered every known Magic in the world and yet the concept of love between a parent and a child still eludes him. August then sadistically asks Gildarts that if Cana were to be killed in front of him how he would feel. This immediately provokes and angers Gildarts.
Gildarts tells August that if he hurts Cana, he will show him a hell that will make death look like a walk in the park. Cana tries to warn Gildarts not to fall for August's bait, but Gildarts does not listen as he charges towards August ready to punch him. However, August easily grabs his fist and throws him to the ground. Gildarts proceeds to kick at the old wizard, who blocks his attacks and blasts Gildarts into a wall of stone. August asks if a parent should love his child to which Gildarts replies that they should as he charges at him. August blasts him, sending him flying through the air. He then questions why the Emperor has never loved his child, while at the same time, Cana jumps into the air, trying to help her father, much to Gildarts' worries. Cana brushes them aside, telling him that she's a grown woman now and throws cards at August, who dodges them. She tells Gildarts to stop being an overprotective father, to which Gildarts disagrees, saying that she will always be his daughter.
Resuming the fight, Gildarts jumps at August, who blocks his attack with his staff, as Cana throws cards at him. August avoids them while Gildarts uses All Crush, blasting it at August. However, the target of the spell is undamaged by the blast and charges at the two, knocking them to the ground. Gildarts comments that none of his magic, not even Fairy Glitter, could work on August, just as the Spriggan 12 Mage tells him that their love ends. He moves to impale Cana with his staff, but Gildarts jumps in the way of the attack, taking the hit himself. Cana screams for her father's safety, however, Gildarts says that the wound is nothing as the same spot that was eaten by Acnologia a long time ago. Cana asks him to stop overdoing everything, which Gildarts tells her that he can't because he is her father, and that she is his daughter. He begins to thrust himself towards August, who asks his opponent if he is insane, while Cana cries over her father's life.
As Gildarts continues to push towards August, the powerful Mage tells him that all Magic will not be able to affect him. However, Gildarts then states that he is already aware of the way his opponent's Magic works: that August can use an advanced Copy Magic which can copy all types of Magic he sees, as well as nullify them. The Fairy Tail Mage reveals this ability's weakness, an inability to copy Holder-Type Magic, which is why he always avoided Cana's magic cards. Cana hears this and throws her Magic cards at August, with each card hitting the Alvarez Mage. Following her daughter's opening, Gildarts uses his prosthetic arms to strike August with his Crushing Evil, Spreading the Truth: Absolute Heaven.
Afterwards, Gildarts realizes that his arm is now immobile from his attack on August. Before they can rejoice, however, August gets up, appearing to have taken no damage at all, shocking Cana and Gildarts. The Spriggan 12 reveals more into why his Magic power is so great, as well as why he considers Zeref his savior. He tells them that even if it costs him his life, he will put it to use in order to destroy the entire country. August then begins to cast Ars Magia, which causes everyone in Magnolia's blood to begin to evaporate. However, just as he spots Gildarts holding Cana and telling her that he will protect her no matter what, he recalls what he told Jellal, that the only person who could defeat the Emperor's son would be his own mother. August then glances at Mavis, who is on the ground, staring at August. The old Mage suddenly stops the spell to save his mother, causing his body to begin to disintegrate.
As August's body disintegrates, Mavis wonders if he has run out of magic power, and if he did, it was because of Gildarts. She then runs off to the Fairy Tail guild hall. A shocked Cana asks Gildarts to confirm Mavis' words, but Gildarts tells her that the Spriggan 12 mage saw something and stopped the spell. Disappearing, August makes his final wish: that just once he wanted his mother to hold him in her arms. Behind Mavis, August then appears in child form as an illusion, shouting "Mother", before disintegrating completely. Mavis stops and turns to look behind her, only to find nothing there.