The air in the engineering room was taut, as if sealed beneath a thin membrane of ice. Caravane Noire—the twelve-car train of black steel, halted at the outer edge of the Seventh Ruin—sat in silence, reflecting the white light of the scorched earth. The only sounds within the cars were the low hum of Absolute Zero's control panel and the rhythmic electronic pulses leaking from the connection apparatus. Kestra Vael traced the rows of numbers on the terminal screen with her sharp, amber, almond-shaped eyes. Her deep crimson hair, bound high in a single tight ponytail, swayed with the faint vibrations of the train. The thin blade scar on her right cheek shifted subtly in the pale glow of the monitor. The self-check had entered its final phase. All circuits of the connection apparatus were synchronized with the control systems of the Plant remnants, and preparations for transitioning to the activation sequence were nearly complete. But—Kestra's finger stopped over a single value. Arisa's biometric monitor. Her heart rate had already reached critical levels, and her blood oxygen concentration had fallen far below baseline. And above all, the composite index indicating her life-support threshold flashed in red numerals. —89%. Kestra stared at that number for several seconds. More than any figure she had seen across all her past missions, this one presented an unambiguous answer. In the next experiment, this girl would die. She turned around. Galen Vollhardt stood in the center of the engineering room. His short, silver-gray hair was impeccably neat, not a strand out of place, and his right eye—a deep, dark navy—gazed down at the control panel. Beneath the black eyepatch covering his left eye, the golden prosthetic implanted with Plant cells gave off a faint, prickling light. The brand on the back of his left hand, the mark of one sworn directly to Knives, reflected the room's lighting with a dull gleam. The index finger of his right hand twitched, ever so slightly. "[cold]Begin the experiment." His voice was flat, as if reading aloud from a report. There was not a shred of emotion in it. Only the command, cast into the chilled air. Kestra did not reply immediately. She picked up the terminal and walked toward Galen. The intricate tattoo of the Plant crest, etched from her left shoulder down to her upper arm, surfaced under the lights. "[serious]Before that, there's a number you need to see." She held the terminal out into Galen's field of vision. On the screen, Arisa's biometric data flashed red. Eighty-nine—that number, cold and clinical, stated only the facts. "[serious]Eighty-nine percent on the life-support threshold. If you force the next experiment in this state, her heart will stop before the authentication is complete. This is a technical fact. Not my opinion. The numbers say so." Her voice was as matter-of-fact as if she were reading off a blueprint. She stripped away all emotion, delivering only a technician's report. Yet her amber eyes never once left Galen's profile. Galen glanced at the value. And then— "[cold]For the fulfillment of the great cause, there are acceptable losses." The index finger of his right hand moved again. "[cold]Proceed with the experiment as scheduled. That is an order." Inside Kestra, something silently crossed its critical threshold. —Acceptable losses. The meaning of those words was clear. In this moment, Galen had made the decision to process Arisa entirely as expendable material. A unique being with an affinity for Plants—a human-shaped manifestation of the very existence Knives had loved—used up and discarded as mere biological parts. It was structurally identical to the acts of humanity that Knives had hated most. Kestra did not answer. Instead, she walked over to the main power panel of the activation device. Her crimson hair swayed, still bound tight. Her slender fingers closed around the heavy, unadorned metal lever. She pushed it down in a single motion. —Clank. A heavy metallic sound echoed through the room, and the pale lights of the control panel winked out, one by one. The numbers vanished from the monitor, the electronic pulses ceased, and the resonant hum of the Plant remnants receded into the distance. The engineering room fell into complete silence. Galen's right index finger stopped moving. "[cold]Kestra, this is insubordination. I will require an explanation." His voice still held its coldness. But faintly—truly faintly—something creaked deep within it. Kestra turned around. Her amber eyes stared directly into Galen's right eye. A subtle distortion touched the corner of her mouth. A peculiar smile, lifting only the right side. "[sarcastic]An explanation? Fine. I suppose I could give you one." She took a step closer to Galen. "[cold]Your great cause—it isn't the continuation of Knives's ideology. It's nothing more than the twisted obsession of someone Knives never acknowledged." The words sliced through the cold air. "[cold]Through that prosthetic eye, you maintain a simulated connection to Knives. But it's not a real connection. It's just remnants. And you treat Arisa as a supplement to that connection—because her Plant affinity lets you delude yourself into feeling Knives's presence." Kestra's voice was sharp as a blade. With a technician's logic, she dismantled Galen's fanaticism piece by piece. "[cold]But that's already the same act Knives despised. Exploiting Plants as tools, using them up and throwing them away—how is that any different from what humanity has always done?" Silence. Galen had no words of rebuttal. His right hand gripped the handle of the Vespyr in the holster at his hip. The large-frame, long-barreled revolver—its cold sensation bit into his fingers. But the finger that would pull the trigger stopped. If he shot Kestra, her technical knowledge would be lost. If that happened, the plan to activate Absolute Zero would collapse entirely. His calculations presented that fact with ruthless clarity. Exactly as calculated. Ironically, his own cold calculation now shackled his actions, if only for this single moment. At that moment—Galen's prosthetic eye shifted, ever so slightly. Toward the direction of the holding cell. An unconscious motion, confirming Arisa's presence. The center of gravity of his emotions exposed itself for just a fraction of a second. Kestra did not miss that movement. Her amber eyes narrowed faintly. —An uncalculated move. "[cold]What did you just look at?" The question did not seek an answer. In that instant— The heavy iron door of the engineering room was flung open with force. "[scared]Reporting!" A soldier from the communications room burst in, breathless. The Plant crest tattooed on his left shoulder glistened with sweat. His voice trembled, his face deathly pale. "[scared]The sentry posts on the outer defense perimeter—three locations have gone silent within the last twenty minutes. No response. None of the posts even transmitted a malfunction report." Galen's expression changed for the first time. —This was not equipment failure caused by sandworms. This was a precise, systematic neutralization by a highly trained, lone infiltrator. Neutralized so instantaneously they couldn't even send a malfunction report. And at three locations. Vash. The name surfaced in his mind. Vash the Stampede—the "Humanoid Typhoon"—the man classified as a natural disaster by insurance agencies, was quietly peeling away the outer perimeter, heading inward. "[cold]Redeploy all forces toward the outer perimeter. Block the intruder's path." "[scared]But—" The soldier's voice shook even more. "[scared]During the relocation the day before, nearly half our forces split off to secure fuel. Our current defensive strength is—less than half of normal." The facts piled up like a triple collapse. The defection of the second-in-command who bore the technical foundation of the plan. The intrusion of an external enemy. And insufficient combat strength. Galen Vollhardt, for the first time, perceived the outline of a comprehensive defeat. His great cause was crumbling here. That fact stood before him as cold reality. "[cold]...Send all forces to outer perimeter defense. I will be out shortly." He left the operations room. His footsteps echoed down the corridor, fading into the distance. Only Kestra remained in the engineering room. She immediately turned to the terminal and began copying the activation data. All information on Absolute Zero streamed into a portable storage medium. This was not insurance against Galen. —By holding the data, she would seize the initiative of the plan. A reconstruction of the project, one that treated Arisa not as a tool, but as a collaborator. That was Kestra's new objective. Her loyalty had ended here, completely. The moment the copy finished— From the direction of the holding cell, a faint resonance sounded. A sound like Plant energy, answering in a subtle call. Kestra tucked the storage medium into the inner pocket of her coat and turned her steps toward the holding cell. She placed her hand on the observation window and checked inside. Arisa was awake. She sat on the cot, her back against the wall, her long, silvery-white hair matted with sweat and dust. Her large, pale aquamarine eyes stared directly at Kestra through the observation window. Deep within those eyes—there was no fear, no hatred, only a quiet understanding dwelling there. As if sensing something, Arisa gave a small nod. Kestra did not respond. She simply closed the observation window, quietly. Their gazes had met for only a few seconds. But it was the first contact of the distorted cooperative relationship the two would later form. □ At the outer edge of Caravane Noire, gunfire began to erupt in rapid succession. Not single shots—the precise, unerring report of Vash's silver gun. And the wild return fire of the Grief soldiers answering it. Shouts, explosions, the sharp metallic ring of bullets piercing armor—the entire train shuddered. The cars began to groan. In the operations room, Galen stared at the tactical monitor. The defensive line was collapsing at a pace far faster than anticipated. The tactical placements he had set were vanishing one after another, displayed on the screen as cold points of light winking out. He took the Vespyr in hand and moved to head for the front lines. At that moment— The door to the operations room opened, and Kestra appeared. She carried nothing in her hands. But the chest of her coat bulged slightly. She made no effort to hide the fact that the storage medium was tucked there. "[cold]The duplication of the activation data is complete." Her voice was as flat as if she were commenting on the weather. "[cold]And this is no longer your plan." Galen understood. Kestra had not betrayed him. She had stolen the plan itself. The great cause he believed in, the technology, the loyalty of his second-in-command, and from the outside, his certainty of victory—all at once, this woman had taken everything. "[cold]The next time I see Arisa, it won't be as a tool." Touching the storage medium lightly, Kestra said only that before disappearing into the corridor, which was beginning to fill with smoke. Galen was alone. It was not anger, nor despair. What remained within him was—only a baseless question: what had he believed in, to stand here all this time? The cage of his great cause crumbled completely around him. From outside the car, fierce gunfire sounded again. The metallic clang of bullets striking armor echoed intermittently. Caravane Noire had finished its countdown to collapse. Galen Vollhardt slowly raised the Vespyr. His silver-gray hair was disheveled by the blast wind. The last remaining thread of his great cause—taking as many enemies with him as possible on this battlefield—was the only calculation left to him now. From down the corridor, he heard footsteps.