CHAPTER SIXTEEN

ATTACK ON THE OCEAN TURTLE, JULY 2026

1

Even Takeru Higa, who was well aware of his first-class genius status, couldn’t have predicted the various events of the last two hours. But what was playing out before his eyes at the present moment was by far the most shocking of them all.

A delicate girl, only eighteen or nineteen years old, was lifting a man six inches taller than her by his collar. His flashy Hawaiian shirt was stretched enough to tear, and the soles of his sandals hung in the air.

As she glared at Lieutenant Colonel Seijirou Kikuoka with radiant fury, Asuna Yuuki’s shapely lips formed a razor-sharp ultimatum. “If Kirito doesn’t wake up, I’ll make sure you regret it.”

From Higa’s position, the lenses of Kikuoka’s black-framed glasses reflected the lights in the ceiling, so he couldn’t make out the man’s expression. But the Self-Defense Force officer, who was a black belt in both judo and kendo, swallowed as though intimidated by her threat. He lifted up his hands in a sign of surrender.

“I know, I know. And as it is my responsibility, I will absolutely see that Kirito is restored.”

A tense silence filled the gloomy sub-control room. Neither Higa, sitting before the control console, nor Rinko Koujiro, who stood next to him, nor any of the other Rath staffers in the room could speak a word before the overwhelming force of the youngest person present. In the back of Higa’s mind, he recognized that she was indeed a true survivor of life-and-death battle.

Eventually, Asuna slackened her grip. Finally free, Kikuoka nearly fell to the floor, exhaling heavily. The girl faltered, too. Rinko leaped forward, white coat flapping, to put a hand on her back for support.

The physicist, who was Higa’s friend and mentor from their college seminar, clutched Asuna to her chest and murmured, “It’s all right. It’ll be all right. He’ll come back to you.”

Asuna’s tension finally broke, and her face crumpled.

“……Yes, of…of course. I’m sorry…I went too far…”

Tears formed at the corners of her eyes; she hadn’t cried even during the attack. Rinko gently rubbed them away.

The mood in the room eased up at last, only for the tension to return when the sliding door opened manually. Lieutenant Nakanishi raced inside.

His white shirt was stained with sweat and dust, and the grip of his large pistol was visible in the shoulder holster. He glanced at the women first, then found Kikuoka in the back and said, “Report, sir! Primary and secondary pressure-resistant barriers are closed, and noncombatant evacuation to stern block is confirmed complete!”

Kikuoka strode forward, fixing his collar. “Thank you. How long will the barriers hold?”

“Well…it depends on what they brought with them, but they are indestructible to small firearms. If they’ve got circular saws, you’re looking at no less than eight hours to penetrate. They could break through with explosives…but I doubt that’s an option. After all, the center barrier is very close to…”

“The Lightcube Cluster,” Kikuoka finished, pushing his glasses up the bridge of his nose.

He stopped to think, then lifted his head and looked around the cramped Subcon room. “Let’s get a picture of the situation. Lieutenant Nakanishi, give me a casualty report.”

“Sir! Three minor injuries to researchers on the civilian project team, recovering in the stern medical bay. Two heavy and two minor injuries to our combatants. They are also recovering, nothing life-threatening. Including the two who sustained minor injuries, we have six sailors in battle condition.”

“It’s a damn fortunate turn of events not to have any deaths, for all that fighting…Next, damage report on the ship.”

“Control room on the bilge dock is Swiss cheese, sir. No way to open or close it remotely. Same for the corridor from the dock to Main Control, but it’s more scratched than anything. The real trouble is that the main power line has been cut…Our power’s still stable because it’s coming through auxiliary lines, but if we don’t reactivate the control systems, we can’t rotate the screws.”

“We’re like a turtle without fins—and with a shark clinging to its belly.”

“Yes, sir. All twelve sectors of the lower shaft and the bilge dock are under enemy control.”

Nakanishi’s chiseled features twisted in frustration. While his hair was close-cropped, Kikuoka had longer bangs like a teacher. The superior officer rested on top of the nearby console and let his wooden geta sandals dangle from his toes.

“So they’ve got Main Control, STL Room One, and even the nuclear reactor…I guess the silver lining is that they don’t seem to be intent on destruction.”

“You…think so, sir?”

“If they just wanted to destroy this facility, they didn’t need a sub and a grand infiltration plan; they could’ve just shot it up with cruiser missiles or torpedoes. So the question now is, who are these people? Any thoughts, Higa?”

Higa blinked, not expecting to have the conversation thrown his way. Eventually, he was able to get his brain running again after the shock of their recent experience.

“Ah. Right. Um…,” he murmured unhelpfully. He turned to his console, grabbed the mouse, and opened up the ship’s security camera footage on the large monitor.

The video clip was dark and unclear, so he stopped it at a random point and adjusted the brightness and contrast. It brought into focus a group of figures moving through the ship interior in a crouching position. They wore black combat suits and helmets with multifunction goggles that covered the top half of their faces, and they carried menacing assault rifles.

“…So as you can see, they’ve got no flags or other identifying features anywhere on their helmets or suits. The color and shape of their gear isn’t official military hardware of any country on Earth. The rifles look like Steyrs, but those are everywhere…About the only thing I can estimate is that, based on their average size, I don’t think they’re Asian.”

“So at the very least, they’re not our country’s special forces. What a relief,” Kikuoka deadpanned. He scratched his chin, his normally gentle eyes narrowed and hard as he stared at the monitor. “There’s one more thing we can tell…These people know about the existence of Project Alicization.”

Higa agreed. “Yes, that would be true. They came in from the bilge dock and raced straight up for Main Control. They’ve got to be after the STL…No, they’re after the true bottom-up artificial intelligence, A.L.I.C.E.”

That meant they’d had a very serious, long-term information leak. But Higa didn’t say that out loud, and he suppressed the urge to examine the faces of every last Rath employee in Subcon, choosing to be optimistic instead.

“Fortunately, we did lock Maincon up in time. In other words, I made it so they can’t directly interface with the Underworld—much more reliable than just smashing the console. They can’t interfere with the simulation or eject the lightcube containing Alice’s fluctlight from the cluster.”

“But the same goes for us, doesn’t it?”

“Sure does. We can’t perform any operations requiring admin access here in Subcon, either. It’s impossible to eject Alice’s lightcube from the outside, either at Main or here…Doesn’t that mean we’ve essentially won, Kiku? They can’t access the cluster either physically or electronically, and once our defense ship cruises in with backup, those punks are toast!”

“I’m not sure what makes them toast…but you’ve actually hit on the problem,” Kikuoka said, frowning. He asked Nakanishi, “Will Nagato come for us?”

“Well…sir…,” Nakanishi replied, lines deepening around his stern jaws, “Nagato has orders from fleet command in Yokosuka to maintain its present distance and remain on standby. Command seems to think we’ve been taken hostage by the attackers.”

“Wha…?” Higa gaped, his jaws open. “Hostage?! But all the crew evacuated to this side of the barrier, right?!”

Kikuoka said calmly, “I suspect those men in black have a channel to the top brass of the SDF. Nagato left the side of the Ocean Turtle at eight hundred hours, six hours before their attack. By the time Nagato gets the order to engage, they’ll already have secured Alice’s lightcube. Of course, they probably have a time limit of their own…”

“So those guys definitely aren’t garden-variety terrorists, then. That’s bad…If they’ve got experts, they might actually be able to figure out the trick to recovering Alice…”

“An operation from within the Underworld, you mean…? They’ve got the first STL room under control, and you can perform the eject command from the virtual console within the Underworld…”

“What happens if you make that command?” Rinko Koujiro asked.

Higa made a gesture with his hands. “The corresponding cube will be extracted from the Lightcube Cluster in the center of the main shaft and sent to the requested control room through the air tubes. That’s where it can be retrieved.”

He pointed at a square hatch in the corner of the console desk and looked at the door on the wall behind it.

The aluminum alloy door had a small metal plate screwed into it. The letters engraved on the plate said STL ROOM TWO.

On the other side of the door were two Soul Translators. One of them was under supervision by the nurse Sergeant First Class Natsuki Aki—it contained a young man. He’d played a major role in Project Alicization since the early stages and was now practically responsible for the outcome of the project itself: Kazuto Kirigaya.

Kikuoka looked forward once more, folded his arms, and said heavily, “Once again, our final hope rests with him…Higa, how is Kirito’s condition?”

There was an intake of breath, and Higa looked at Asuna Yuuki, who was still being held upright by Rinko. Their eyes met.

She was the girlfriend of Kazuto, aka Kirito. How could he explain the present situation? While it was hoarse, her voice was firm.

“I’m fine. Please, tell me the truth.”

Higa took a deep breath, exhaled, and said, “Summed up as briefly as possible…he’s holding steady one step short of the worst-case scenario…Miss,” he said, trying to soften the blow.

He grabbed the mouse and took down the still image of the attackers, opening a new window instead. This one displayed a colorful, three-dimensional graph that swayed and rolled gently.

“This is a visualization of Kirito’s fluctlight,” he explained. Everyone in the room stared at the screen in silence. “In Tokyo, one week ago, he was injected with a muscle relaxant and fell into cardiac arrest. He did survive, fortunately, but he suffered brain damage…technically, fluctlight-network damage. It’s something that existing neural medicine finds very difficult to treat, but there is the possibility of recovery with the STL. So we put Kirito into the STL without any limitations, hoping it would prompt the growth of a new network and restore his fluctlight to wholeness.”

He took a breath and grabbed a bottle of mineral water off the desk, quenching his dry throat after the unfamiliar act of continual talking.

“In order to make use of this treatment, he needed to dive into the Underworld. It won’t take hold unless the fluctlight is active the same way it is in the real world. So like we did when he went on a test dive at the Rath office in Roppongi, we blocked his memories and dumped him into the outer regions of the Underworld…or we tried to. For reasons that remain unclear, probably having to do with the damage to his fluctlight, his memories weren’t blocked. Kirito was sent into the Underworld as himself—Kazuto Kirigaya. And we didn’t know this until we received his contact from within the simulation…”

“W-wait a moment,” interrupted Rinko. “Are you saying that in the Underworld, with time accelerated, he’s been living as himself, as Kirigaya? For…how many months…?”

“…About two and a half years.”

Higa’s answer caused Asuna to twitch in Rinko’s arms. It was a shocking thing for her to hear, no doubt, but he had to trust in her earlier reassurance.

“For all that time, Kirito’s been around artificial fluctlights in the Underworld. And probably with the knowledge that they are bound to be erased with the conclusion of the current simulation…So he would have headed for the console that makes contact to the real world, which is located in the center of the Underworld, where the first village was installed. To petition you to preserve all the fluctlights, Kiku.”

Higa glanced sidelong at Kikuoka, whose glasses reflected the graph on the screen he was reading. The researcher turned back to Rinko and Asuna.

“…It couldn’t have been an easy task,” he continued. “The console was incorporated into the base of a ruling organization known as the Axiom Church. The fluctlights belonging to the church have absolute numerical superiority, far beyond any common citizen’s, which is what Kirito was assigned to be. Normally, he should have died soon after infiltrating the church and gotten logged out of the Underworld…but instead, he survived. I couldn’t check the event log while the attack was going on, but it turned out that he had a number of helpers—artificial fluctlights, of course…He had friends. Most of them died in the battle against the church, but when he finally succeeded in opening the circuit to the outside, he was strongly blaming himself. In other words, he was attacking his own fluctlight. Just then, our shady attackers cut the power line, and the momentary power surge caused an instant spike in the STL’s output. The result was that Kirito’s self-destructive impulse was actualized…and his ego was deactivated…”

“What do you mean…his ego was deactivated?” Rinko asked.

Higa turned to the console. “Just look at this.”

His fingers flew across the keyboard, enlarging the real-time graph of Kazuto Kirigaya’s fluctlight activity. At the center of the erratically undulating rainbow-colored cloud, there was a small, persistent void, like a dark nebula.

“Unlike a fluctlight contained in a lightcube, a human being’s organic fluctlight is still far from being fully understood, but we’ve still got a pretty rough map of the structure. The part here, at this black hole, is what should normally contain the subject…the self-image.”

“Meaning…the actualization of the self, as determined by the individual?”

“That’s right. When we express our will, it happens through simple yes/no logic pathways in the fluctlight: whether I will or will not do this thing in this situation. For example, Rinko, have you ever ordered seconds at a beef-bowl restaurant?”

“…I haven’t.”

“Even if you wanted to or thought you had the room?”

“Correct.”

“So that was the result spit out by your self-image pathways. Virtually none of our decision-making leads to proper action unless it happens through those circuits. In Kirito’s case, the majority of his fluctlight is unharmed. But because the area in question isn’t functioning, he cannot process exterior input, and he cannot output his own actions. I would guess that all he’s capable of is…reactions, things based on traces of familiar, rote memories. Eating, sleeping, things of that nature.”

Rinko bit her lip, considering this for a moment. Then she whispered, “And…what is the status of his conscious mind right now?”

“…I’m afraid to say…,” Higa started to answer, then paused and looked away. “He might not be aware of who he is, or what he should be doing…unable to say or do anything…”

Yet again, silence filled every inch of the melancholy control room.