Visitor Arc IV is the fourth episode of the second season of the Mahouka Koukou no Rettousei anime.
It turns out that the masked magician that fought with Erika was Lina. With her identity blown, Lina uses the Parade spell to attack Tatsuya and a skirmish ensues. Both parties receive reinforcements and things quickly escalate. In the aftermath intel is attained and given to the other parties hunting for the 'vampires'.
Tatsuya dispels Sirius’s Parade revealing her true form as Lina. Lina immediately attacks with her gun, but Tatsuya calmly decomposes the bullets and makes the gun fall apart and tries to get her to stop but his words fall on deaf ears. The fight escalates, with Tatsuya analysing her Parade while they exchange blows. Deciding it restores too quickly, Tatsuya decides to end the fight by throwing a grenade into the air.
The grenade detonates, and though both raise defences, Tatsuya has to use Regrowth to heal the damage he takes from the blast, and then charges Lina before she can react and pins her to the ground. Tatsuya begins to remove her mask, and Lina desperately activates Dancing Blaze to stop him non-lethally, but he simply decomposes them. Lina tells him he’ll regret removing the mask, but Tatsuya simply points out he already regrets letting the parasite he shot escape.
Unmasked, Lina immediately screams that she’s being attacked, and Tatsuya is immediately surrounded by four police officers. Tatsuya rips off Lina’s CAD glove as he stands up with her restrained. One of the officers demands Tatsuya surrender at gunpoint. Tatsuya thrusts Lina into him and jumps into the air, lands on the officer, and then kicks him in the face, knocking him unconscious.
Tatsuya the turns around to see the other four looking shocked at what happened and tells Lina to drop the charade, using her code name. Lina apologises and acknowledges his resolve my introducing herself formally and asks that he address her s Lina whilst not using her disguise. She then states now she’s been unmasked he has to die as her companion rearms her. Before they have chance to resume the fight, Miyuki interrupts and freezes two of the men, whilst Kokonoe Yakumo appears from behind Tatsuya, having incapacitated the third.
With Lina surrounded three-on-one, Tatsuya states he has some questions and offers her the option of a one-on-one duel and if she wins, she can go, if she loses then she answers some questions. Lina agrees but Miyuki interjects, insisting on being the one to duel Lina, explaining she considers Lina a rival, but cannot forgive an attempt on Tatsuya’s life and gives Lina a murderous glare as she states Lina must be punished for her sin. Lina shows confidence she can win, asking if Miyuki really thinks she has a chance. Tatsuya agrees to let the pair handle it.
After changing location, Tatsuya reassures Lina they will honour the deal. Yakumo declares he will act as the judge, stating the rules are to fight until one side surrenders or is incapacitated but killing is disallowed. Tatsuya asks them to wait a moment, and walks over to Miyuki, and kisses her on the forehead, releasing the Pledge to return Miyuki’s full control of her magic. Tatsuya then returns to Yakumo’s side, though Lina is in disbelief at the intimacy the two Shibas shared.
The duel begins but before Lina can act, she’s hit by Miyuki’s first attack and forced to defend. Miyuki then baits Lina verbally and she falls for it, charging in. Miyuki activates her Deceleration Zone and Lina is forced to defend again. Lina releases a button to confirm the trap, so Miyuki reactivates her offence. Lina counters with Molecular Divider and then Dancing Blaze, but Miyuki counters, thanking Tatsuya for returning her control as she would have lost to that attack. There is a brief pause in the duel as Lina is shocked by the fact Miyuki could defend, assuming it was simply down to Tatsuya tipping her off during their ‘moment’ before the duel. Deciding to bet it all on an all-out attack, Lina casts Muspelheim, which Miyuki counters with Niflheim. The two spells fiercely compete, but as Lina starts losing, Tatsuya ends the match by dispelling both spells, and causing a huge explosion, shocking everyone.
The duel over, Miyuki runs over to check Tatsuya is OK, as he was hit by the blast, though Miyuki cast a spell to protect him. Yakumo emerges from the ground, followed by his two disciples, and asks why Tatsuya interrupted the match. Tatsuya states the no killing rule would have been broken had he not acted. Lina comes over and admits she lost but agrees to only give yes or no answers because of Tatsuya’s interference.
Next morning, a sullen Lina is dragged out of bed by Silvie. After finishing having a breakdown, Silvie gives Lina some reports, first informing her one of the injured from last nigh will have to return home and be replaced. Silvie then tells Lina that there are no Stars available so they may send Stardust instead, but Lina is unimpressed, thinking they won’t be able to handle the work. Silvie informs Lina that the other team has had no results, leading Lina to inquire about Mia. Silvie informs Lina that Mia will be delivering equipment to First High tomorrow and will be free to have lunch, much to Lina’s delight.
At a party in the USNA, Shizuku is joined by Raymond Clark. After some pleasantries, the pair head outside where Raymond tells Shizuku that the parasite incidents are true and appear to be related to a secret Micro Blackhole experiment near Dallas, the parasites having been first observed just after its completion.
Back in Japan, at First High, Erika and Mikihiko are waiting for Tatsuya, having been summoned by him. The pair are shocked when Saegusa Mayumi and Juumonji Katsuto arrive and Tatsuya arrives just after with Miyuki. Once Mayumi and Katsuto have sat down, Tatsuya informs them he has intel to share on the parasites and lays out the facts.
First, he implanted a radio transmitter into the parasite last night and it will emit a signal every three hours for the next three days. It can be tracked by the roadside cameras. The others try to ask questions, but he ignores then and gives them cards containing the details of the signal.
Second, he tells them that the parasites are deserters from the military and that there are at least two and as many as ten or so. Erika comments ten people deserted Stars, but Tatsuya corrects them stating that is not the case and Katsuto explains that the Stars are an elite unit from the military. Mikihiko wonders how it could happen and Tatsuya explains it’s likely the influence of the parasites exceeded the influence of military discipline, commenting they could have altered their minds as well as their bodies, warping their sense of values.
The intel given, Erika asks what the next step is, and Tatsuya states he’s not going to tell anyone what to do. So long as the matter is dealt with he doesn’t care who or how it’s done. Tatsuya then leaves with Miyuki, leaving the other four alone.
On the way home, Miyuki notices something is bothering Tatsuya and gets him to admit he’s feeling guilty as he could potentially have avoided Leo’s hospitalisation if he’d just acted rather than ignoring everything to avoid their daily lives being impacted when he knew Lina was plotting something. This pleases Miyuki, who comments on Tatsuya’s kindness and explains Tatsuya is upset Leo was hurt and didn’t want to hurt Lina as they are now friends and she’s happy because it means he can show compassion for people other than her, his emotions being more human than he thinks. Tatsuya gets embarrassed by this and tries to hide it, much to Miyuki’s amusement.