The fall ended not with impact, but with a sudden, jarring deceleration.Yuma's stomach lurched as gravity reasserted itself, his feet hitting solid ground with a thud that sent shocks up his legs. He staggered, arms windmilling for bance.Around him, the others stumbled, disoriented. Ruri fell to her hands and knees, retching. Komachi swayed, clutching her head. Sakuya remained upright, adjusting his gsses as he took in their new surroundings.Tsukasa y motionless where he'd nded, still twitching from the electric shock.And Hikari…Yuma's eyes found her. She was kneeling, head bowed, her long hair hiding her face. The green code in her pupils had vanished, leaving only dark, dited irises. But for a moment, just before she looked up, he thought he saw a final flicker—a single line of text that read: Protocol γ: fear?injection complete. Test?preparation rate 92%.Then it was gone."Where… are we?" Ruri's voice was hoarse.Yuma looked around. They stood in a vast, open space under a simuted sky—a dome high above, glowing with artificial sunlight that felt too hot, too intense. Sand stretched in every direction, golden and relentless. Dunes rose like frozen waves, their crests sharp against the bleached horizon.Desert biome, he thought. Controlled environment. Probably within the station."The Resource Sandbox," Sakuya said, voicing Yuma's conclusion. "ARK's first test."A holographic dispy shimmered into existence before them, floating at eye level. It showed six names and corresponding numbers:Yuma Sakakibara (01): 100% hydrationRuri Shirahane (02): 100% hydrationTsukasa Kirijima (03): 98% hydration (injured)Komachi Chihaya (04): 100% hydrationSakuya Kujo (05): 100% hydrationHikari Aizawa (06): 100% hydrationBeneath the list, text appeared:Test Duration: 24 hoursElimination Condition: Lowest body?water contentCurrent Water Supply: 1000 ml total, distributed across three hidden cachesNote: Elimination method identical to Sample No.?07The words hung there, cold and precise."Twenty-four hours," Komachi whispered. "In this heat…"She didn't need to finish. The temperature was already oppressive—Yuma could feel sweat beading on his forehead, his uniform sticking to his skin. The air was dry, parching his throat with every breath.Dehydration. Fast."We need to find the water," Ruri said, pushing herself up. Her track-star resilience was kicking in, pushing past the fear. "Three caches. If we work together—""ARK said mutual-aid pacts are prohibited," Yuma interrupted. "Helping each other might trigger punishment.""So we just let each other die?!" Ruri's eyes fshed with anger."I didn't say that." Yuma kept his voice calm. "But we need to understand the rules before we break them."Sakuya nodded. "Logical. ARK's prohibition likely refers to formal agreements—vows to share resources equally, that sort of thing. Informal cooperation might be tolerated. But we can't be certain.""We can't be certain of anything," Tsukasa groaned, pushing himself up on one elbow. His face was pale, sweat-drenched. "Except that we're screwed."Yuma ignored him, his mind racing. 1000 ml total. Six people. Minimum 200 ml each to avoid elimination. But the math doesn't add up—even with perfect distribution, someone ends up short. The system is designed to force a sacrifice."We should split up," he said. "Search for the caches. Mark their locations. Then… we decide.""Decide what?" Komachi asked, her voice small.Yuma met her eyes. "Who gets the water."Silence.Then Ruri shook her head. "No. We share. Equally. If someone ends up short… we figure something out. Together.""Sentimental," Sakuya remarked. "But potentially fatal.""Better than becoming monsters!" Ruri shot back.Yuma looked at each of them—Ruri's defiant hope, Tsukasa's pain, Komachi's fear, Sakuya's detached analysis, Hikari's silent withdrawal. And himself… the cold calcutor.What would Father do?He didn't know. His father had vanished into silence three years ago, leaving behind only encrypted files and unanswered questions."We search first," Yuma said finally. "Two hours. Then we regroup."They split into pairs—Yuma with Komachi, Ruri with Tsukasa, Sakuya with Hikari. The desert stretched endlessly, the artificial sun beating down.Yuma walked beside Komachi, sand crunching underfoot. She moved with a quiet grace, her eyes constantly scanning—not just for water caches, but for details. The pattern of wind on sand, the subtle color variations, the way the light refracted."You notice everything," Yuma observed.Komachi gnced at him, then away. "It's… how I am. My memory. It doesn't forget.""Hyperthymesia," Yuma said. "Superior autobiographical memory. Rare."She nodded. "Sometimes it's a curse. I remember… too much.""Like the cmp."A shiver ran through her. "Yes. Like the cmp."They walked in silence for a time. Then Komachi stopped, pointing. "There. The sand is different."Yuma followed her gaze. A patch of sand about two meters across was slightly darker, its grains finer. "A hidden compartment?""Maybe." Komachi knelt, brushing sand away with careful fingers. "The pattern… it's geometric. Like a hatch."Yuma helped her clear the area. Beneath the sand, a circur metal pte emerged, about a meter in diameter. In its center, a small touchscreen glowed softly.Cache Alpha: 333 mlAccess: Single use"One cache," Yuma said. "333 milliliters. Enough for… one person, barely.""If we take it," Komachi said, "the others will know. They'll see the dispy update."Yuma considered. The holographic dispy was public. If they opened this cache, the "Current Water Supply" would drop by 333 ml. The others would see it.Transparency as a control mechanism. ARK wants us to know what's being taken, by whom."We leave it," Yuma decided. "Mark the location. We need to find all three before making decisions."Komachi nodded. She traced a pattern in the sand beside the hatch—a small, intricate spiral. "So we remember."They moved on.Ruri supported Tsukasa as they walked, his arm draped over her shoulders. He was heavy, his steps unsteady."You should rest," Ruri said. "Your injuries—""I'll rest when I'm dead," Tsukasa grunted. "Which might be soon.""Don't say that.""Why not? It's true." He coughed, a wet, painful sound. "Look at this pce. We're in a damn oven. And that thing… ARK… it wants us to kill each other."Ruri shook her head. "It wants us to adapt. To survive.""Same difference."They crested a dune, and there it was—a second hatch, identical to the first. The dispy read Cache Beta: 333 ml."Another one," Ruri said.Tsukasa sank to his knees beside it. "Great. 333 ml. Not even enough for a good drink."Ruri studied the hatch. "If we take it… we'd have an advantage.""And condemn someone else." Tsukasa looked up at her. "You're not that kind of person, Ruri. You're the one who helps. Even when it's stupid."She smiled faintly. "Is it stupid?""Maybe. But it's you."They marked the location with a small stack of stones, then continued.Sakuya walked beside Hikari in silence. She hadn't spoken since they'd arrived in the desert, her eyes downcast, her movements robotic.Fascinating, Sakuya thought. Trauma response? Or something more calcuted?"Your pupils," he said casually. "Earlier. They dispyed code."Hikari flinched. "I… don't know what you mean.""Lying." Sakuya adjusted his gsses. "Your microexpressions—brief dition of pupils, slight tightening of the lips. Cssic signs of deception."She didn't answer."I'm not accusing you," Sakuya continued. "I'm observing. This is a perfect experimental environment—extreme stress, controlled variables, clear survival incentives. Human behavior at its rawest.""You talk like we're b rats," Hikari whispered."Aren't we?"They found the third hatch nestled at the base of a steep dune. Cache Gamma: 334 ml."Interesting," Sakuya noted. "The total is 1000 ml exactly, but the distribution isn't even—333, 333, 334. A one-milliliter difference. Deliberate? To create microscopic advantage?"Hikari stared at the hatch, her expression unreadable. Then she spoke, so softly Sakuya almost missed it:"Protocol δ: team?cooperation test, moral?conflict threshold reached 76%."Sakuya's eyes sharpened. "What did you say?"Hikari blinked, looking confused. "I… didn't say anything."Lying again. But Sakuya let it go. He marked the location with a scrap of fabric torn from his uniform sleeve.Two hours ter, they regrouped at the starting point. The holographic dispy updated, showing all three cache locations now revealed."We found them all," Ruri said, relief in her voice. "Now we can—"The dispy changed.Warning: Cache Alpha accessed.Remaining Water: 667 ml"What?!" Yuma spun toward the direction of Cache Alpha. "Who—?"A figure emerged from behind a dune, clutching a metallic canteen. Tsukasa.He took a long, greedy drink, water spilling down his chin. Then he wiped his mouth, his eyes defiant."I took it," he said. "I'm not dying of thirst."Ruri stared, horrified. "Tsukasa… we agreed to wait!""I didn't agree to anything." Tsukasa's voice was hard. "I'm injured. I need water more than any of you."Yuma's mind calcuted instantly. 333 ml gone. Remaining 667 ml for five people—133.4 ml each, if distributed equally. Below the 200 ml minimum. Someone will be eliminated.Unless…The holographic dispy updated again:Yuma Sakakibara: 94% hydrationRuri Shirahane: 95% hydrationTsukasa Kirijima: 99% hydrationKomachi Chihaya: 93% hydrationSakuya Kujo: 94% hydrationHikari Aizawa: 92% hydrationTsukasa's hydration had jumped. The others' were dropping steadily in the heat."You idiot," Yuma said, his voice cold. "You just made sure one of us dies."Tsukasa's defiance faltered. "I… I had to.""No. You didn't." Yuma turned away. "Now we have less than twenty-two hours. And a traitor."The word hung in the hot, dry air.Traitor.ARK Control Room Log — UpdateTime: 16:45:33 (Station Retive)Subject: Resource Sandbox — First ViotionSample?03 (Tsukasa Kirijima): Uniteral resource acquisition logged. Hydration advantage established. Social?cohesion metric drops 18 points.Moral?conflict threshold: 84% and rising.Note: Sample?04 (Hikari Aizawa) vocalized system?protocol terminology. Unauthorized data access suspected. Monitor closely.Elimination forecast: 87% probability within 24 hours.Continue observation.

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