With Irene's Universe One changing all of Fiore with the sole purpose of ending the war and acquiring Fairy Heart as soon as possible, Invel joins Zeref at the new Fairy Tail guild, where the emperor confronts Mavis. He swiftly freezes the girl as to ensure that their objective doesn't escape, however, after Zeref's protests, he instead chooses to imprison her mind. Taken outside by Zeref afterwards, the first master witnesses the mighty Spriggan 12 gathering as the ultimate battle formation.
Meanwhile, the forces of Fairy Tail are getting their final rest before the final battle and with the next day starting, Gray and others charge straight into the enemy army in order to create a path for everyone else. After some time, as Gray's group continues to crush the enemy soldiers, Natsu prepares to shoot his Roar, but as soon as his flames are unleashed, they are frozen solid. The Dragon Slayer turns to Gray, but the Ice-Make Mage denies the blame, however, noticing the temperature dropping as Lucy and Juvia complain about the cold. Natsu surrounds the area with his flames in an attempt to counter it, but his fire once again freezes and the culprit makes an entrance: Invel enters the battlefield, with Gray noticing that all of his friends have completely turned to ice.
Invel expresses a slight surprise over the fact that Gray's body seems to be immune to this cold, with the latter getting into a position to unleash his Ice-Make. However, he is suddenly thrown into a nearby ruble as Invel, with a simple gesture of his hand, hits Gray with an icy attack. Gray witnesses the part of his body that got hit with the attack to be covered with ice, but before he can do anything, Invel continues his spree with several spiky objects made of ice and, as Gray falls down under the barrage of attacks, the Winter Mage introduces himself to a shocked Gray, claiming the Ice-Make Mage's ability to be nothing before his winter. Invel then launches yet another icy attack, but this time, Gray anticipates it, protecting himself with Ice-Make: Shield and finally goes offensive, creating Ice-Make: Ice Impact to hit invel from above. Much to Gray's surprise, Invel freezes his attack and causes the ice hammer to crumble, pointing out the difference between their abilities: Invel doesn't create object out of ice, but uses the ice to freeze everything instead.
Seeing that his regular Ice-Make has no effect, Gray challenges Invel by activating the power that his dad left for him: the black markings of Ice Devil Slayer Magic appear over his body and Gray charges at his opponent, striking him with Ice Devil's Zeroth Long Sword at great speed, shocking Invel. Gray grabs the sword and slices Invel once more, with the Winter Mage's surprise growing as he realizes that Gray is using a power that destroys Demons while taking the user's soul as a price. Invel smiles over this development and finally block Gray's attack and then unleashes a huge amount of Magic, covering the whole area with a blizzard. While Gray notes that it's cold enough to freeze, Invel praises Gray and his ability, considering the two of them equal. However, he points out that Gray's being tainted by darkness, comparing it to the powers of Zeref himself. Not wanting to listen to any of this, Gray exclaims that it doesn't matter how much darkness he has to go through, as long as it is to protect his family.
That is when Natsu finally breaks free from Invel's ice, praising Gray for his Fairy Tail-like way of thinking. While Invel smiles, recognizing Natsu's power for being able to melt the ice, Lucy and Juvia also join the fray, but suddenly, Brandish, in the form of a giant, appears, taking Natsu, Lucy and Happy away. Gray attempts to intervene, but suddenly, a collar is put around his neck. Invel, with a motion of his hand, does the same to Juvia, connecting the two with a chain between the collars. Suddenly, Gray states that he is unable to think properly, with Juvia joining in with a statement of her body not moving as she wants it. Invel explains that this is the effect of Ice Lock, intending to use it to seal the hearts of Gray and Juvia in order to make them fight each other. While the two are shocked upon this revelation, with Juvia thinking that she'd rather fall herself than hurt Gray, Invel already has his plan thought out: Gray will be victorious and through killing his own comrade, his darkness will awake in order to slay E.N.D.
Unable to control their thoughts and movements, both Gray and Juvia soon charge, blasting each other with their respective Magic. They then move to hand-to-hand combat, exchanging kicks and punches, however, Gray soon overpowers Juvia, throwing her to the ground. Witnessing this, Invel is assured of his calculations being correct, being under the belief that he is watching the birth of a warrior that shall defeat Zeref's strongest Demon. Meanwhile, Gray and Juvia continue clashing, with the latter cursing herself for hurting Gray, trying to come up with a solution for this situation while she is still able to produce thoughts in her controlled mind. She figures out that letting Gray to beat her up isn't plausible, as he'd just blame himself for that, so she becomes set on one, final way out of this mess. Invel continues to show off his smile, claiming that no matter what they try to do, the chain between them won't break until one of them dies. However, Juvia turns to Gray, thanking him for all the time they have spent together and covers her hand with a blade of water, using it to stab herself afterwards. Invel's shock only grows as Gray reaches the same conclusion, stabbing himself with a sword of ice. Both question each other's actions, with Gray claiming that he can't even think of hurting Juvia, this statement causing the latter to tearfully smile. As they fall to the ground, bleeding from their wounds, Gray wishes for Natsu to avenge them.
Invel then watches as both of his enemies lie on the ground, realizing the grave error in his calculations. As the chain connecting Gray and Juvia disappears, Invel walks away, taking the responsibility as the one to destroy E.N.D. The blizzard that has been covering the battlefield finally disappears and Gray slowly regains his consciousness. He notices a certain feeling, something that he soon identifies as Juvia's blood flowing into his own body. Completely destroyed by this realization, Gray holds Juvia's motionless body, screaming in pain and sadness and begging Juvia to open her eyes. A few moments later, Invel, who is still looking for Natsu in order to destroy him, feels a strange presence. He turns back just to witness Gray, completely enraged, approaching him.
Unable to believe that Gray is still alive, Invel states that the Fairy Tail Mage shouldn't be able to make use of his strength with such injuries, however, he is soon proven wrong as Gray immediately runs to his opponent, punching Invel into his face, following by several more blows that throw Invel into a nearby wall. The Winter Mage quickly gets up on his feet, realizing that he needs to use his trump card: he covers the entirety of his body with an armor of ice, something that freezes anything it comes into contact with, according to Invel's words. As Gray attempts to strike Invel, he realizes the truth behind Invel's words, however, even though his body begins to freeze and crack, he manages to destroy a portion of Invel's armor, much to his shock. As Invel realizes that Gray has managed to make use of the same ice that his armor is made of, Gray covers his arms and fists with it, delivering several destructive punches, which causes the defeat of the Winter General.
Meanwhile, Juvia also regains consciousness, just to hear Wendy telling her not to move yet. Carla states that they have found Juvia just in time to help her, with Wendy pointing out that it was only thanks to Carla's Precognition ability. Realizing that she is still alive, Juvia gives Wendy her sincere thanks. After Juvia's delusions of being kissed by Gray are disapproved by Carla, Juvia suddenly notices that Gray is nowhere to be found, with Wendy and Carla knowing nothing about his whereabouts either. At the same time, Gray talks to a defeated Invel, claiming that no matter what he does to Invel, Juvia isn't coming back. Invel confirms that and follows by saying that the same goes for all those that have left the world before Gray. He states that while E.N.D. is here, Gray's life will be full of misfortunes. Just as Gray responds that he will be the one to defeat the Demon, Invel finally reveals the true identity of the Etherious to Gray: it is none other than Gray's close friend, Etherious Natsu Dragneel.