“Y-you couldn’t have…defeated the Four Gods and opened the four gates?” Koto asked ever so timidly.

After exchanging a quick glance with Trilead, Crow shook his head firmly. “No. It would be absolutely impossible for us to defeat any one of the Gods.”

His voice contained a chilling fear now, as if the previous feigned innocence had been a dream, and Koto held her breath again. Crow looked to the Black King and, perhaps getting permission through eye contact, continued.

“Last month, we went on a mission to rescue Ardor Maiden. She’d been sealed at the Castle’s south gate for a long time—she’d fallen into an unlimited EK. The plan was for K—I mean the Black King to get the south gate’s guardian, the God Suzaku, to target her, while me and Master…I mean Sky Raker charged the altar in front in a two-stage booster. Ardor Maiden would appear at just the right time, and I’d catch her and bring her back out. But the instant I grabbed hold of her, Suzaku started to target us. I couldn’t turn, so we had no choice but to charge into the gate. And it was open just a little bit, so we slipped in through the gap.”

“The gate was open?” Yuki muttered, dumbfounded. “Even though the Four Gods hadn’t been defeated?”

“Each of the Castle’s four gates has a seal on the inside that matches its respective guardian beast,” Trilead told her. “It’s set up so that defeating the guardians destroys the seals. But from the inside of the gate, it is possible to destroy the seals with a physical attack.”

“…What…?” It was all Koto could do to get that single word out.

As a veteran Burst Linker, she had assumed that she well understood the presence of the Castle and its importance. But now she was painfully aware that she had never once thought of the fortress rising up in the center of the Unlimited Neutral Field as a tangible target for attack. But the members of the Black Legion were different. Of course, there was the fact that their executive members were sealed away at the four gates. But rather than simply saying “It’s the Castle” and giving up, they’d investigated and then investigated the investigations, hammered out a strategy, and finally slipped past the guard of the Gods to succeed in the great enterprise of entering the Castle, a feat no one from the six Great Legions had ever managed.

Honestly, who are these people? Koto groaned to herself, not in the voice of Cobalt Blade but that of her own flesh-and-blood self, before pulling herself back together and giving voice to a new question.

“But in that case, when Crow and Maiden approached the south gate, someone had to have already destroyed the seal disc from the inside…Isn’t that what you’re saying? Otherwise the gate wouldn’t have opened, yes?”

“Yes.” Trilead nodded before stunning the sisters again. “I was the one who cut the seal. However, I wasn’t working in concert with Crow’s mission. I did this out of the vague hope that someone might come in through the gate someday.”

“Come in…through that gate?” This wording deeply puzzled Koto. It almost sounded as if Trilead Tetroxide could normally dive freely inside the Castle—he couldn’t have been locked up there or anything, right?

She was about to question him further, but before she could open her mouth, Trilead shook his head.

“Please excuse me. I still can’t answer your question yet, Cobalt Blade. If there were one thing I could say…It’s because Crow opened the Suzaku gate and came flying inside that day that I am able to come outside like this after being in a certain sort of confinement in the Castle for a long period.”

“Th-that’s—I mean, same here,” Crow put in immediately. “If you hadn’t smashed the Suzaku seal for us, Lead, the gate wouldn’t have opened and we would’ve been stuck in an unlimited EK.”

“No,” Trilead counterprotested. “Breaking through Suzaku itself has to have been any number of times more difficult than destroying the seal.”

“Not many more times.” The silver avatar shook his head. “The soldier Enemies in the Castle are superstrong, and they keep popping up forever.”

The Black King abruptly giggled. “Just as I’d heard, you make a good combo.”

“Huh?” Silver Crow turned to his king. “H-heard? From who?”

“Maiden and Raker, of course. Trilead, please keep being a good friend to Crow.”

“Gah! What are you saying, K—?!”

You two make a nice combo, too. Koto forced herself to keep this thought to herself and sorted through the information in the back of her mind. As long as Trilead Tetroxide himself wouldn’t talk about his mysteries, she couldn’t pursue it any further. But the bits of information that he had supplied were so astonishing they made the core of her mind go numb.

At present, ownership of only three of the Seven Arcs was known: The alpha, Impulse, was owned by the Blue King; the beta, Tempest, by the Purple King; and the gamma, Strife, by the Green King. These had been discovered in the deepest levels of the so-called four Great Dungeons in the Unlimited Neutral Field. But only the empty dais of the delta, the Luminary, had been found in the underground labyrinth at Shiba Park; no one knew who had taken the Arc. And legend remained that the zeta, the full-body armor Destiny, had been polluted by dark Incarnate at the dawn of the Accelerated World and transformed into the Armor of Catastrophe, Chrome Disaster.

Silver Crow, who sat now beside Koto drinking tea, had been the sixth Chrome Disaster, but he broke the curse and sealed the Armor away in some corner of the Accelerated World. Or at least, that’s what he had announced at the meeting of the Seven Kings the previous month. Which meant that he had to know the whereabouts of the Enhanced Armament that had once been the zeta, but just as with Trilead’s secrets, she knew he would never tell her, even if she asked nicely. And Koto wasn’t the least bit interested in knowing where that fearsome armor slept, anyway.

In short, the only Arcs whose names and locations were not known were the epsilon and the eta, and every high ranker had spent long years chasing after them. And now, in the place where she sat quietly having tea, it was finally clear that the fifth Arc, The Infinity, had been inside the Castle and Trilead Tetroxide had obtained it. Which implied that the zeta had also been in the Castle, enshrined alongside the epsilon, which in turn meant that the first Chrome Disaster had gotten into the Castle through some means other than defeating the Four Gods to get the armor. So then the seventh—the final Arc—also had to be inside the Castle. And perhaps no one could touch it yet?

“Silver Crow,” Koto started, ready to check if her assumptions were correct. However, she faltered the instant those mirrored goggles turned toward her. She felt awkward casually asking about the seventh Arc, the greatest secret in the Accelerated World. She turned instead to Black Lotus across from Crow. “Black King. Why would you reveal such critical information to the executives of a hostile Legion? The seal structure of the four gates is information of greater value than the strategy for the gimmicks in the four Great Dungeons.”

“The executives of a hostile Legion?” The Black King turned a gaze so gentle on the twins that Koto almost disbelieved it possible for her to have driven the Red Rider to total point loss with a single blow before going on to attack the other kings. “Well, Leonids do attack Suginami area every so often even now, so I suppose in terms of position, that is what you would be. But in that case, I’ll just ask: Why did you accept Crow’s dangerous and troublesome request? I would have thought it only natural to refuse something like moving all the way to Minato Three in the real world to check the matching list.”

“…Well…” Koto was surprisingly at a loss for words.

“I’ll tell you right now,” Yuki replied, somewhat thornily. “We didn’t give our word without due consideration of the past and the future. It was only after we crossed swords with Silver Crow and then came face-to-face in the real, after we carefully tested how serious he was. And the Acceleration Research Society is our problem, too. If the White Legion is suspected to be the real group behind them, we have to lend a hand at least. Even if the request comes from an enemy Legion.”

Black Lotus remained lazily amiable. In fact, when she opened her mouth again, she even seemed to be smiling slightly. “When I received the report on this matter from Crow, I was more surprised that you had met them in the real than I was that you’d accepted our request. At any rate, if you’ve fought in the Accelerated World and eaten a parfait in the real world, then you’re no longer an enemy, are you?”

“So if we’re not enemies, then what are we?!” Koto demanded, childishness flaring up without her meaning it to.

“Friends, of course,” the Black King replied neatly.

“Fr—” Normally, she would’ve grabbed the hilt of her sword the instant she heard the word and yelled about not underestimating her. But she had almost never heard the word friend in the Accelerated World, and for some reason it pierced her heart now.

In the family restaurant in Nakano, they had sat down not as armored warriors Cobalt Blade and Manganese Blade but as ninth graders Koto and Yuki Takanouchi with the flesh-and-blood Silver Crow/Haruyuki Arita and Ardor Maiden/Utai Shinomiya and talked over strawberry parfaits. She hadn’t been tense or nervous at all then. Just the opposite, in fact. After she and Yuki got home, she had even thought it would be nice to do something like that again, although she’d never felt like that toward her comrades in the Blue Legion before, much less members of a hostile Legion.

Struck by the Black King’s words, her mental defenses crumbled, if only for an instant, and Koto turned her gaze toward Silver Crow. “Are we…your f-friends?” she muttered, only to kick herself a moment later for asking such a dumb question.

“Huh? Um…Oh!” The silver duel avatar also stammered, sounding bewildered, but eventually he nodded firmly. “Yes. I think we’re friends.”

Koto and Yuki couldn’t remember having had anyone they could attach the priceless tag friend to in the real world since finishing elementary school. The reason for that was probably the fear that had penetrated deep into their hearts that they might not be the real them. Since they had set their individual hairstyles, there was no longer that immediate confusion about who was who, but the faint unease that welled up each time a classmate called “Koto” or “Yuki” hadn’t gone anywhere. The pressure of this left them unable to open up to anyone, and children were sensitive to such things. The twins were more and more often left out of the group, and they put on a show of strength, acting as if it didn’t matter so long as they had each other. This mental-scar “shell” didn’t completely disappear after they received their unique names as Burst Linkers, and they hadn’t been able to blend into their classes at school over the last three years. At some point, they’d gotten used to it, and just when they’d thought it would keep going like that after they went on to high school, they were hit with this declaration of friendship from Silver Crow.

““……””

Speechless for a full five seconds, Koto and Yuki cleared their throats at the same time, apparently on purpose.

“W-well, if you say that, we might do that for you,” Yuki started. “That…The whole f-friend thing.”

“B-but don’t get carried away,” Koto warned with a sigh. “We’re at best all Burst Linkers. When we find the names on the list, we’ll charge in without hesitation.”

Silver Crow bobbed his head up and down at top speed, and the Black King let slip a faint smile for the nth time.

“Hee-hee. I’m simply glad we’ve reached a consensus. Now I can answer your previous question. I disclosed the information about the Castle to you, Dualis, because you are Crow’s friends.”

“Th-that’s it?” Koto asked, stunned.

Black Lotus shrugged. “Do I need anything else?”

“……”

Koto was struck dumb, wavering between exasperation at this recklessness and admiration at the impressiveness of a king.

“Hee. Hee-hee…Ha-ha-ha-ha…” Trilead Tetroxide abruptly burst into laughter. The young, sky-blue samurai laughed for a while, sounding like a cool breeze blowing through, before composing himself and bowing. “P-please excuse me. I apologize. I was simply thinking the way the Black King speaks, she truly is Crow’s parent.”

“Oh-ho!” Black Lotus nodded. “That’s a glad thing, then.”

“Huh?” Silver Crow cocked his head. “Y-you think so?”

Instantly, the light in the Black King’s eyes grew sharp, and she raised the sword tip of her right hand as she pressed her child for details. “And what does that mean, Crow?”

“N-no, it doesn’t mean anything!” He waved his hands in front of his face.

“So that wasn’t how you really feel just now?!” she snapped. “Do you hate people thinking I’m your parent?!”

“N-n-n-n-no, I’m telling you that’s not it! I just couldn’t say anything as cool as you!”

Trilead started giggling again, and as she watched, Koto felt something rise up from her own throat. Unable to withstand it, she let it out and was surprised to discover that it was loud laughter.

“Ha-ha-ha! Ha-ha-ha-ha-ha!” As she doubled over, she glanced to her side and found Yuki laughing the same way, in the same position.

When exactly was the last time we laughed like this? she wondered as the bright laughter of the twins echoed through the Wasteland stage.

Koto and Yuki left the two members of the Black Legion at the stone table with Trilead Tetroxide to conduct their Legion entry procedures, and then headed for the JR Meguro Station nearby (transformed into a sandcastle) to return to the real world through the portal.

Letting out a sigh, Koto cut the global connection on her Neurolinker and opened her eyes just as the bowl-cut boy was raising his face a millisecond after the twins.

So it wasn’t just Silver Crow and Ardor Maiden now; they’d been cracked in the real with Trilead Tetroxide, too. But strangely, no feelings of alarm welled up in her. She didn’t particularly want to go so far as to exchange real names, but she did wish him luck in the Territories with her eyes.

The boy bowed deeply and stood. It was still seventeen minutes before four o’clock, and since the actual battle probably wouldn’t start exactly at four, he was probably planning to move to another location in the building and dive into the Territories stage from there.

After watching Trilead leave the café, Koto wet her throat with her still-cold mixed berry soda and turned her gaze on her twin sister.

Yuki stuck out her tongue playfully. “Friends, he said.”

Koto was stuck for a minute on how to react as the older sister. “So then we have to do something friend-like. Once this issue’s taken care of, let’s have parfaits together again.”

“I was just thinking the same thing!”

The sisters exchanged a giggle, and then looked up together at the summer sky as it started to take on a faint golden color.