by Shouji Gatou
“Guess,” Sousuke said shortly.
“Guessing complete. Do you wish to hear my conclusion?”
“No.”
“Roger. Please provide a rating of this machine’s autonomous battle function.”
“Well done. That is all.”
“Learning message: explain the meaning of ‘well done,’” the Arbalest requested.
“Figure it out,” Sousuke barked back. “And shut up until I give further orders.”
“Roger. Though I would prefer not to.”
“I told you to shut up.”
“Roger.” With that final rejoinder, the Arbalest’s AI fell silent.
Kaname, who was quietly listening to the exchange, found herself thinking what a strange operator—AS combination they were. It vaguely reminded her of the way conversations between her and Sousuke typically went. And with that realization, it all made sense.
The lambda driver-mounted AS was designed to shadow its operator as closely as possible. It could intuit the operator’s psychology and emotional state, and synchronize with them, not by copying, but by complementing. The further that process progressed, the more efficient the machine’s dynamic response rate with the omnisphere would become. This meant that while their enemies could only execute what was programmed into them from the start, the ARX-7’s potential was nearly limitless.
The one who made the machine—Tessa said his name was Bani—he must have been very talented, with a real romantic spirit... Kaname could tell that he’d loved Tessa, as well.
“Chidori?” Sousuke’s voice snapped her out of her reverie. The train of thought disappeared in a flash.
“Huh?” she said.
“How are you? Were you hurt?”
“Ah... no. I’m okay,” she told him. “But where’s everyone from school? And we need to get Tessa—” Suddenly, a new train of thought jolted through her, stopping her mid-speech.
Kaname-san. I’m sorry to interrupt again. I see it went well... I’m glad. But I’m afraid something awful has happened. Please send medics to Area H21 in the starboard corridor. There’s a man there, Sailor-san. He’s injured, and he will require a significant blood transfusion. He will die if nothing is done.
“Tessa...?” she asked uncertainly.
I’d ask you to send my men to the C16 observation deck, as well... but I know that it won’t be in time. Harris is finalizing his preparations to escape with me. This might be the last time we speak.
“Tessa?” Kaname tried again, through a rising sense of alarm.
I hate how powerless I am. If only I had your strength... Please, be of use to everyone. You’re the only one who can replace me. And regarding your relationship with Sagara-san... ah... it’s fading...
“Tessa?!” Kaname yelled, but that was the end of their resonance. A stinging in her right cheek, the pain of handcuffs on her wrists, and an afterimage of that captain’s sinister grin were all that remained with her.
5: Sleepless Christmas Eve
24 December, 2335 Hours (Japan Standard Time)
Shark-1, Near Izu Islands
Shark-1, having collected information about the enemy from the sonobuoys he’d dispersed in advance, observed the pathetic attempts at evasive maneuvers being taken by the Tuatha de Danaan. They’d probably be changing heading and speed frequently to try to scramble their target motion analysis.
Stupid, he scoffed to himself. Do they really think those textbook submarine tactics will work against Leviathans?
Shark-1 opened his encrypted channel for shallow depths and issued orders to his wingmen: “B240, D300, Code 13. Heading 240. Navigate to depth 300 and attack target from three directions. You have permission to use ultrafast torpedoes.” Ten seconds later, he received a signal of acknowledgment from both machines, and the ‘first officer’ sitting behind him activated their fire control system.
The Leviathan’s arsenal included Soviet-made ultrafast torpedoes known as Buryas. Their top speed was 120 knots, over twice the speed of the standard torpedoes used in the West. They were effectively missiles, and not even the Tuatha de Danaan could shake them off.
His AI revealed via on-screen display that the enemy had entered firing range. His two comrades were almost there, too. The de Danaan might be agile for a submarine, but it would still be helpless against attacks from multiple Buryas, coming from three directions at once.
Shark-1 removed the final safety and pulled the trigger. He felt a jolt as the ultrafast torpedo took off out of the firing tube in the Leviathan’s belly, on a collision course with the de Danaan. Easy. It’s too easy... he thought with a thin smile.
Next, he started preparing another weapon for the area the Pacific Chrysalis was in; a standard torpedo would be more than enough for that one. He had no idea who was on board that ship, and he didn’t especially care. He’d been ordered to destroy it, so he would.
Tuatha de Danaan
The de Danaan’s officer of the deck, Captain Goddard, could feel his heart pounding in his chest, even as he remained superficially calm. He couldn’t stop feeling that they were facing hopeless odds. Just minutes ago, he’d been sure that nothing in the ocean could tangle with this vessel when it was in top condition. And yet, now...!
The enemies were running at over fifty knots, and it was three against one. Their top speed was probably greater than the Tuatha de Danaan’s. And worst of all, they were flaunting the ironclad law of combat. He’d never expected them to sneak up in secret and attack them from behind.
They want to take us down fast, huh? he thought with resignation. To approach at unthinkable speeds, slam them with all the power they had, then rush away from the area of engagement, all in mere minutes... This enemy could do things that normal submarines couldn’t. Goddard would find it implausible, if he hadn’t experienced the capabilities of the de Danaan first-hand.
Any way you looked at it, they were at an overwhelming disadvantage. Against small boats with the maneuverability of torpedoes, the de Danaan felt impossibly large and unwieldy. If this situation was presented as a training exercise, everyone would agree it was a no-win scenario. It was utterly unprecedented.
Goddard peered over at his XO, Lieutenant Colonel Mardukas. The other man stood ramrod straight at the center of the control room, silent, with a melancholic expression. He was probably using the data they’d acquired to extrapolate the capabilities of the enemy vessels.
That grave expression of his was making Goddard feel more and more anxious. What’s going on here? he wondered. The enemy’s movements were straightforward, boasting absolute confidence in their victory. How could they be so haughty? Did the weapons they carried also defy common sense?
The sonar tech spoke, as if to respond to Goddard’s unasked question. “Con, sonar! Torpedo in the water! Bearing 0-4-9! From Mike-13!”
“Can you give me the type? And the speed?” Mardukas prompted, seemingly unfazed by the threat of enemy attack.
“Wait a minute... no way! It’s too fast! Over 100 knots?! This torpedo is impossible! What in the world...”
“A Burya,” Mardukas decided.
“Burya?” Goddard questioned, and scowled at the XO’s words.
“An ultrafast torpedo made in the USSR,” Mardukas clarified. “It creates a bubble of gas around itself and is propelled with a rocket motor. It’s likely wire-guided. I suppose the intelligence division does their jobs right from time to time.”
“B-But XO, even if we know what it is, we can’t shake it off at that speed.”
“It would be stranger if we could shake off a torpedo. It’s nothing to worry about.”
“But...!”
Mardukas glared at Goddard. “Calm down, Captain. Your panic is annoying me, and if I get annoyed, we all go down. I’m afraid I don’t have time to explain every element of my plan, so stop thinking and follow my commands, quickly and to the letter.”
“Y-Yes sir,” Goddard responded.
“Good. Now, make our course 1-3-6, and gradu
ally increase to sixty knots. Don’t worry about cavitation. Open the door for the third torpedo tube and release all safeties.”
“Ah... Aye, sir.” Each position repeated the orders.
《Estimated sixty seconds to impact.》 The Mother AI, undergoing complicated TMA calculations, began the countdown to their doom.
As if to punctuate her words, the sonar tech screamed, “More torpedoes! One each from Mike-14 and Mike-15! They’re both ultrafast as well! Bearings 0-6-8 and 0-8-9!”
The enemy torpedoes currently bearing down on the de Danaan were on another level from the ones that the US Navy submarine had fired at them near the Perio Islands. It would be hard enough to dodge just one... and now they had three incoming from all different directions.
Time was short. They had only about fifty seconds left. But as far as Goddard could see, Mardukas wasn’t panicked in the slightest. He just glared at the multipurpose screen, like a cryptologist deciphering a line of code. All the data available suggested no way out. But, Goddard thought, is the XO seeing something we aren’t?
“Up to fifty knots.”
“What’s the course of the torpedo from Mike-13?” Mardukas wanted to know.
“2-2-1.”
Right now, the de Danaan was running perpendicular to the enemy torpedo. The enemy weapon was gradually adjusting its course to better home in on them.
“Forty seconds left!”
Then Mardukas said, with the nonchalance of someone ordering off a restaurant lunch menu, “It’s time. All stop. Left full rudder, course 0-4-5.”
“Aye, sir! All stop! Left full rudder! Course 0-4-5! ...Wait, what?!”
Despite following the orders to the letter, nearly everyone in the control room went pale at the command. Mardukas had turned them on a course straight at the oncoming torpedo. “Fire control,” he continued calmly. “When we reach 0-4-5, fire torpedo three.”
“But at this range, the safeties—”
“Five degrees more.”
“Aye, sir! Fire three!”
The torpedo launched from the tube, and Mardukas continued to give orders out swiftly. “All start, full reverse. Activate EMFC.”
“Full reverse!”
“EMFC, contact!”
The large vessel abruptly slowed. As the torpedo they’d shot screamed away from it, the submarine stopped, and began to move backwards. But the enemy’s ultrafast torpedo was already on their doorstep.
Is he trying to shoot down an ultrafast torpedo? Goddard turned pale at that thought. It was impossible to use one torpedo to intercept another one moving that quickly. Water pressure limited the radius wherein a torpedo’s explosion was effective, so while fragments and shockwaves could make anti-air missiles effective over several meters, a torpedo had to score a direct hit to do any damage at all. It was like a batter trying to hit a 150 kilometer-per-hour fastball, blindfolded, using sound alone. The XO must know that. But then, why—
“All hands, brace for impact,” Mardukas said calmly over the ship phone, and then gripped the armrest of the captain’s chair beside him. Goddard quickly did the same.
On the front screen, the marks showing the approaching enemy torpedo and the one they had just launched closed distance. They were now just a few seconds apart.
“FCO. Are you calm?” Mardukas asked.
“Y-Yes sir!” the fire control officer replied in falsetto.
“Good. Detonate torpedo three,” Mardukas ordered. “Now.”
“Aye, sir!”
Their torpedo detonated right in front of the enemy’s... and right in front of their own vessel, causing the explosion’s roar and shockwave to rip through the Danaan. It bucked as if taking a few hundred jabs from a boxer, jostling the already tensed crew. Goddard felt his heart nearly leap from his chest. As he gripped his own chair tightly, his eyes flicked searchingly around the front screen.
The counterattack had failed. It hadn’t reached the enemy torpedo when it exploded. White noise from the foam created by the explosion meant they couldn’t confirm its presence, but it had to be out there, and still speeding towards their ship...
By their calculations, one second left—
“Next, halt reverse course. Forward, two-thirds speed. Course 0-6-7. Move to periscope depth,” Mardukas said through the commotion, as if he’d already moved on to the next phase of combat.
“What?” The whole crew, including Goddard, couldn’t believe their eyes. The ultrafast torpedo was gone; all the data on hand made that clear. Their torpedo hadn’t hit it, and yet...
“We’ve cleared the first. The second and third are still coming. We’ll deal with them in the same manner,” Mardukas instructed. “Then, just as you counter, fire MAGROCs to the surface from all MVLSes. Set the coordinates just as I tell you. Understand?”
Shark-1
Shark-1’s captain was shocked. An explosion from an enemy torpedo had caused the Burya he’d launched to self-destruct. “Impossible... they knew about that?” he asked incredulously.
It was one of the Burya’s few weaknesses: to move a torpedo at such tremendous speeds, it needed to negate drag from the water around it. This was accomplished through supercavitation—wreathing itself in a membrane of foam. The result was a delicate balance; at certain distances, the impulse currents from an explosion could throw it off course and render it unable to fly straight, like a plane going into a tailspin.
Once that balance was lost, the Burya would lose its resistance to water pressure, and its own speed would break it in half. And the commander of the Tuatha de Danaan had known...
Before Shark-1 could even react, the enemy vessel moved, and took out their other two Buryas the same way. He could hear the explosions play out from afar, like a deafening underwater capriccio. The discord of millions and millions of bubbles made it impossible to hear anything the de Danaan was doing.
Not good... They were basically blind. First, they had to slow down to eliminate their own noise generation, then listen carefully. Shark-1 called for an all stop. Once the noise from the currents had faded, and everything returned to silent darkness around them, he could resume gathering data from the sonobuoys.
He didn’t know exactly where it was, but he knew the de Danaan must still be out there. It had to be hiding somewhere near where the explosions had occurred. But the minute it attacked, they’d know where it was.
“Be careful. If we find them first, we win.” The ocean, echoing with cacophony just seconds ago, was a dark, silent void once more. His two wingmen slowed down with him and switched to silent running.
“The foam around the enemy ship has cleared. Let’s turn the sonobuoys to active and find their location,” his first officer suggested from behind.
“Right,” Shark-1 agreed. “It’s not as if they can hurt us. Hunt them calmly.” They’d gotten past the Buryas commendably, but the same trick wouldn’t work twice. If the enemy tried to attack, that would give away their location, and this time, they’d fire a shot they couldn’t dodge. They could even fight them in melee range, if they had to. Either way, the enemy boat would end up as sea scrap.
“Wasting our time... heh.” Shark-1 let out a brief chuckle, then picked up a new sound. It was five loud splashes, coming from all around his two allies, Shark-2 and Shark-3.
Something was descending from above.
“MAGROCs?! When did they—”
MAGROCs were anti-submarine missiles. They could be fired from beneath the water like Tomahawks or Harpoon missiles, and after flying swiftly out of the sea, they’d plunge back into it, activate sonar, and track and destroy enemy submarines.
The de Danaan must have fired a large number of MAGROCs at some point. Normally, they’d have been able to pick up on the sound of the enemy firing a flurry of missiles like that out of the water—the sound would be deafening, after all—and they’d be able to wait and easily dodge them before they hit, forcing the enemy into a stalemate.
But Shark-1 hadn’t detected the sound of the de Dana
an firing the missiles. The enemy must have masked it behind the explosion of the Buryas. They’d used those few seconds when the shockwave was still rocketing outward and the sea was filled with chaotic noise—
“Impossible...” A shiver went through Shark-1’s captain as he realized the cool-headed audacity of the enemy commander. His allies, caught unawares, never stood a chance. The torpedoes caught them in a net. The targeting, landing just a few meters away, had an almost godlike precision to it.
Shark-2 and Shark-3 didn’t even get to make use of their prodigious maneuverability as the de Danaan’s MAGROCs blew them to pieces. That much was clear from the merciless sounds of explosions and noise echoing from behind him.
“A-All ahead full. Course 2-7-5. If we stay here, the MAGROCs will hit us, too!” he declared to the first officer behind him. He had to force his mind to a different topic, so as not to be distracted by his frustration.
It was fine either way, he decided. He’d already launched an ADCAP at the cruise ship. It was a normal torpedo and not a Burya, but it would be enough for a civilian passenger vessel. That would have less than five minutes until impact, and his primary mission was as good as achieved. The Pacific Chrysalis would sink, taking its hundreds of passengers with it.
So will the de Danaan, he promised himself. I’ll have my revenge.
“We’ll approach from the north and hit it with our remaining torpedo,” Shark-1 suggested. “If it dodges that, we’ll close in at high speed and seal the deal with the melee arms.”
“Got it,” his first officer agreed. “Let’s teach them a lesson.”
“The enemy’s out of cards. Let’s do it!”
That was an unexpected setback, but I’ll show you. One Leviathan is still enough to destroy de Danaan...
Tuatha de Danaan
“Mike-13, contact reacquired! Bearing 0-3-1! Acceleration started on course 2-0-5!” the sonar tech reported, unable to hide his agitation.