Large-Scale Invasion Arc

The Large-Scale Invasion Arc is the 4th arc of the series.

A New Model
The invasion begins with Trion Warriors attack the city. In the school, Osamu instructs the students to evacuate with the teachers, and Chika and Natsume to help the evacuation. Yūma accompanies him to fight the Trion Warriors. Due to the Warriors having an outwards direction in attack, Shinoda splits the units, and sends Jin and Amō to the northwest. Traps are used to delay the Warriors until Suwa Unit and Kuruma Unit arrive. Azuma Unit and Kuruma Unit both encounter a new Trion Warrior.

The new model proves to be overwhelming, as it constantly counters all attacks against it. It manages to overwhelm Azuma Unit, forcing Koarai to Bail Out. With the intel from Azuma, Replica determines it's a Rabbit, a new model being developed in Aftokrator. It's so powerful that a lone A-Class agent would not be able to defeat it. The Rabbit's purpose is to capture Trigger users. Aside from it's already-powerful abiltiies, it cubifies Suwa. Kazama Unit takes over.

While discussing the possibility of the Rabbit being overwhelmingly powerful with Kido, Shinoda declares that he may step in.

Kazama Unit fights the Rabbit, albeit with difficulty. After receiving a hit from it, Kikuchihara manages to determine the strongest and weakest spots. Meanwhile, humanoid Neighbors begin to watch Border's battle with the Rabbits. They discuss the power, the captain, Hairein asserts that "Miden" still didn't show its full ability. Meanwhile, Osamu continues to fight many Trion Warriors, only to be overwhelmed by the sheer number. Replica explains that the elimination of the Warriors would take place one-by-one, endangering the evacuations like with Chika. Before Osamu can take action about it, a Rabbit confronts him. However, Yūma uses his Black Trigger to destroy the new model, despite the implications. However, Chano Unit attacks him, believing him to be a hostile Neighbor. The Rabbit, having not been destroyed, attack Chano, however, Arashiyama Unit saves her. At that point, Trion Warriors attack the HQ, only for Tachikawa to attack them. Osamu asks Shinoda for permission to assist Chika and the other C-Class members. Kido authorizes Osamu's doing so, but not Yūma's, as he may be mistaken for the enemy. Kitora accompanies Osamu.

Reaching the scene, they encounter a Mod Rabbit and a Mole Mod. Osamu battles the Mole Mod, defeating it, and Kitora battles the Rabbit. The Mod Rabbit overwhelms her at first, forcing her to dismember her leg to defeat it. From its body, three Rads come out, and summon three other Mod Rabbits. One cubifies Kitora. The rest attack Osamu and the other C-Class agents, but they are saved by Tamakoma First, Border's strongest unit. Tamakoma First easily takes out the Trion Soldiers sent to capture Chika, but the humanoid Neighbors join the battle.

The Humanoid Neighbors
Lamvanein encounters the B-Class union near the Old Mikado City University and attacks them. Using his Trigger Chelidon, he easily overwhelms them, taking out Chano Unit entirely, and wiping out members of different units. As things become bleak for them, Lamvanein prepares to go support Hus and Visa. Midorikawa, Izumi, and Yoneya counterattack him. With information from Kunichika, they manage to get him into a tight space. He does eventually manage to trap Midorikawa inside the building. Midorikawa quickly slashes a fire extinguisher and uses the gas as a smokescreen. He then cuts off Lamvanein's leg, forcing him to be in constant flight. Using the flight to his advantage, he rains down bullets on the teams, injuring quite a few. He decides to take them down one-by-one, and has Kuruma as his first target. While flying towards Kuruma, Yoneya jumps down, attempting to ambush him. However, Lamvanein turns over, and shoots at Yoneya. Midorikawa, Yoneya, Teruya, and Kakizaki combine their shields to protect him, and he proceeds to stab Lamvanein. Lamvanein reverts to his normal body, and is retrieved by Moira.

Enedra appears before Kazama Unit. He attempts to use his Trigger to launch sneak attacks, but Kikuchihara's Side Effect renders them worthless. Seeing that his method of attack was ineffective, he acts frustrated, to lure Kazama, who believes he is frustrated. Kazama beheads him, but Enedra reconnects his head to his body with his liquefaction, and then sprouts blades from inside Kazama's Trion body. Due to the extensive damage, Kazama is forced to Bail Out. Enedra taunts Kikuchihara and Utagawa, but Kazama orders them to retreat. Reluctantly, they do so, leaving Enedra disappointed and even hungrier for killing.

Jin greets Yūma who was taking down Trion Warriors with Arashiyama Unit. He informs Yūma of the current situation, and the possible ways the future could turn out. When Yūma asks what the worst is, Jin reveals that it is Osamu's death. To prevent this, they would have to do their part in fighting it.

Kizaki and Karasuma engage in a shootout with Hus. While fighting, Kizaki and Karasuma use Viper to distract him, while Konami attacks from behind, only to be blocked by Visa. Konami notes that his Trigger gave her a bad feeling. Visa insists that they move on, so Hus uses his Trigger to attach a metal shard to Chika. He then begins to drag her to him remotely. Karasuma attacks Hus again, and Kizaki punches Hus through his thin shield. Kizaki himself gets shard in his arm, though he manages to deduce that Hus's Trigger used magnetism to repel and attract. Kizaki orders Karasuma and Osamu to take Chika away since it was dangerous for her to stay near.

Konami continues to attack Visa, but to no avail since he is too powerful. He then reveals Trion Warriors to head out of the Danger Zone. Kizaki orders Konami to pursue them, while he handled the humanoids. Jin notices that the situation got more difficult. Enedra uses his Trigger to intrude HQ. He attacks the operator's room, killing a couple of them and injuring some others. Hairein chides Enedra for attacking the HQ, stating that it was not as ordered. Moira asks if she should retrieve him for being defiant, but Hairein says no.

Kizaki fights Hus, using traps to attack him. His goal is not to defeat the humanoid Neighbors, but rather to stall them. To finish the battle, Visa uses Organon to cut up his surrounding, forcing Kizaki on the defensive for himself, but he is weighed down by the magnets in his arm. He dismembers his arm, but Visa sends an attack past his shield and defeats him. Kizaki Bails Out. With their opponent gone, Hus and Visa uses Lampyris to speed to Chika. Karasuma, Chika, and Osamu are at a remote entrance to Border, but it doesn't open since all the doors were locked following Enedra's intrusion. Before Hus and Visa can reach them, however, Yūma and Jin intercept them. Yūma fights Visa and Jin fights Hus. Visa initially holds an overwhelming advantage over Yūma to his generally more powerful Trigger and greater experience. While Yūma is able to use chains and mock-Lead Bullets to hold him down, he cannot land any devastating attacks on him. Jin fights Hus with fairly even progress on both sides. Hus brings the battle into a dark underground tunnel to use his advantages of camouflage and invisibility and manages to pin Jin to a wall. Hus tries to deliever the finishing blow to Jin but Jin traps him in Escudo.

Enedra proceeds to attack HQ more, but Suwa Unit (which include a recovered Suwa) responds by shooting at him, aggravating him. They lure him to the training room, which allows Suwa and Sasamori to fight him while immune to his attacks since they can regenerate. Additionally, his Trigger could be analyzed for weaknesses. However, Enedra manages to attack them from the inside with his blades and leave them there so that they couldn't regenerate. By this time, his Trigger has been analyzed by Border. It allowed him to liquefy and gasify his body, immunizing him to attacks. The gas could be used to enter someone's body and attack them from the inside. However, this left his Trion vitals exposed in shells. To make up for this, he had dummy shells. In order to counter this weakness, Shinoda himself goes to the training room and attacks Enedra so quickly that he has no time to create dummies, and all the dummies are destroyed. This allows Suwa to tag the shell with the Trion vitals. The AC is also turned on to nullify Enedra's gas, however, he shifts position and comes upwind, so that Shinoda would breathe in gas and attacks Shinoda from inside. While it appears he has the advantage, Kikuchihara and Utagawa attack him, having been hiding inside the training room with Chameleon the entire time. Since his weak spot was pinpointed, he is defeated and reverts to his normal body. Moira appears, seemingly to retrieve him. However, she dismembers his hand and takes his Trigger, revealing that he was no longer necessary, and kills him. Shinoda orders Kikuchihara and Utagawa to inspect Enedra's corpse to see if any information could be gathered.