The thing about survival, Sekitanki discovered, was that it didn't leave room for existential crisis.
Three days in the Carboniferous, and the questions that had plagued him for years—Why am I empty? What's the point? Does anything matter?—had been replaced by simpler, more urgent inquiries: Where is water? What can I eat? Will that shadow overhead kill me?
Philosophy was a luxury for people who weren't being hunted.
He'd found a relatively defensible position on the third day—a rocky outcropping that rose above the swamp like a broken tooth. The stone was some kind of sedimentary formation, already ancient when the world was young, offering elevation and sight lines that let him see threats before they saw him.
The bone spear had saved his life twice already. Once against another centipede—smaller than the first, but still large enough to crush his ribcage. Once against something he couldn't classify, all segmented body and snapping appendages, that had lunged from murky water while he tried to drink.
Both times, he'd won through desperate improvisation rather than skill. Luck wearing the mask of technique.
But luck ran out. Everyone knew that. It was mathematical certainty.
He needed more than luck. He needed shelter. Real shelter. Something that could protect him while he slept, because sleep—despite his best efforts—kept claiming him at random moments. Microsleep, maybe. Or brain damage from oxygen toxicity. Either way, closing his eyes for even seconds in the open was suicide.
The outcropping would have to become home.
Sekitanki spent the afternoon gathering materials, moving in careful circuits around his chosen territory. Dead wood—not the soft, rotting kind that dominated the swamp, but harder pieces from fallen club moss trees. Broad fern fronds that could serve as roofing. Mud mixed with fibrous plant matter that might work as primitive mortar.
His hands had stopped bleeding days ago. Now they were just scarred maps of his desperation—cuts layered over cuts, some infected, some healing into thick calluses. He barely felt new injuries anymore. Pain had become background noise, like the eternal chittering of the forest.
I'm adapting, he thought, and wasn't sure if that was triumph or tragedy.
He worked through the failing light, racing against the moment when the Carboniferous night would transform from dangerous to lethal. The nocturnal predators were worse—larger, more aggressive, drawn by anything that moved or breathed or made the mistake of existing.
By the time darkness fell completely, he'd constructed something that generously could be called a lean-to. Wooden supports wedged into rock crevices. Fern fronds layered like roof tiles. Mud packed into gaps. The whole structure looked like it would collapse if a strong wind hit it.
But it was his. The first thing he'd built with his own hands since childhood, when his father had helped him construct a robot from cardboard boxes. Before physics. Before everything.
The memory arrived sharp and clean: his father's laugh, genuine and warm, when the robot's head fell off. That's okay, Hankō. Try again. Building things means failing until you don't.
When was the last time his father had laughed like that around him? When was the last time he'd given him reason to?
Sekitanki pushed the thought away and crawled into his shelter. The space was cramped—barely two meters deep, one meter high—but it felt safer than anything since the time machine. He could see the forest from his position. Could watch for approaching threats. Could stab outward with the bone spear if something tried to enter.
The chitin blade he kept beside him, wrapped in fabric strips. His grandfather had called swords katana no tamashii—the soul of the samurai. These weren't swords. Weren't elegant. Weren't even particularly well-made.
But they were his soul now. The only thing standing between existence and extinction. The attack came at midnight. Sekitanki had been drifting in that space between waking and sleep, listening to the night sounds—the rhythmic chirping of cricket-things the size of small dogs, the distant crashes of something massive moving through the canopy, the wet sounds of the swamp digesting itself.
Then: silence. Absolute. Complete. Every animal instinct he'd never known he possessed screamed danger. He gripped the bone spear and waited.
The first scorpion came from the left—a dark shape flowing over rock like liquid shadow. Sekitanki saw the curved tail first, stinger dripping something that caught moonlight and glowed faintly green. The creature was two meters long, low to the ground, moving with the patient inevitability of a hunting cat. Behind it: another. And another. And—
Oh god there's a dozen of them.
They moved in coordination, spreading out to surround the outcropping. Pack hunters. Or colony hunters. Whatever term applied to scorpions hunting in groups that shouldn't exist for another few hundred million years of evolution.
Sekitanki's mind raced. The shelter had one entrance. They could block it, wait him out, sting him the moment exhaustion made him stupid. Unless I don't let them. His grandfather again, voice cutting through panic: In kendō, you do not wait for your opponent to strike. You create the opening. You force the moment.
Sekitanki exploded from the shelter. The nearest scorpion was three meters away. It reared back, tail whipping forward—Sekitanki was already moving, rolling left, the stinger punching into earth where he'd been. He came up stabbing, bone spear driving into the soft junction of It's body.
The scorpion convulsed. Greenish ichor sprayed from the wound. The creature's tail lashed wildly, nearly catching him—Sekitanki yanked the spear free and dove backward as another scorpion lunged.
This one was faster. Smarter. It feinted with its tail, then struck with its pincers. The right claw closed around Sekitanki's arm—pain. White-hot and immediate. The pressure was incredible, chitin grinding against bone. He screamed and stabbed downward with the chitin blade, driving it into the joint of the claw. Something snapped. The pressure released.
Sekitanki stumbled back, clutching his arm. Blood ran between his fingers. The scorpion chittered angrily, one claw hanging useless. Nine more scorpions circled. This is it. This is how it ends. But even as the thought formed, another voice rose beneath it. Quieter. Harder. The voice that had kept him working through sleepless weeks, that had driven him to solve problems everyone said were impossible.
Not yet. Not like this.
He shifted his grip on the bone spear. His injured arm hung nearly useless, but his left was still strong. Still capable. The scorpions attacked together.
What followed wasn't battle. Wasn't even really fighting. It was survival distilled to its purest form—movement without thought, reaction without decision. Sekitanki became something else, something that existed only to continue existing.
He jabbed at eyes. Swept legs. Used the rock face to protect his back. When one scorpion got too close, he kicked it—actually kicked a prehistoric scorpion the size of a wolf—and felt ribs protest but didn't stop moving because stopping meant dying.
The bone spear broke on the fourth kill. The tip snapped off inside a scorpion's head, lodged in whatever passed for its brain. Sekitanki didn't have time to collect resources. He grabbed the chitin blade with both hands and kept fighting.
Cut. Dodge. Stab. Roll.
His body moved in patterns he'd never learned but somehow knew. Muscle memory from a species that had survived by refusing to die. Blood inheritance from ancestors who'd faced predators and won through nothing but desperate will.
This is what humans are, he thought in some distant corner of his mind still capable of thought. This is what we've always been. Not the smartest. Not the strongest. Just too stubborn to accept extinction.
The fifth scorpion fell. The sixth. The seventh. The remaining three broke off, retreating into the darkness with the universal understanding of predators who'd discovered prey that cost too much to kill.
Sekitanki stood in the center of the outcropping, surrounded by corpses, covered in blood—his and theirs—gasping in air that still felt too thick, too rich, too alive. His legs gave out.
He sat down hard on the stone, chitin blade still gripped in shaking hands, and started laughing. The sound was broken. Unhinged. Barely human. He'd survived. Again.
Impossibly, stupidly, through nothing but sheer luck and rage and the refusal to be eaten by giant bugs. The laughter dissolved into something that might have been crying, might have been more laughter. He couldn't tell anymore. Didn't care. He was alive. For now. For another day. For however long the universe decided to let him keep breathing.
Dawn came slowly, green light filtering through the canopy like water filling a tank. Sekitanki hadn't moved from where he'd collapsed. His body was a map of new injuries layered over old ones. His right arm had swollen to twice its normal size, the puncture wounds from the scorpion claw probably infected. His ribs screamed with every breath. His hands were raw meat.
He should feel terrible. Should be wallowing in pain and despair. Instead, he felt... awake. More awake than he'd felt in years. Maybe ever.
The emptiness was still there—that void at his core hadn't magically filled itself. But something had changed. Before, the emptiness had felt like absence. Like something was missing and he'd never find it.
Now it felt like space. Room for something new. He just didn't know what yet.
Sekitanki forced himself to stand. His body protested. He ignored it. Pain was just information now. Useful data about which parts of him were damaged, but not a reason to stop moving.
He surveyed the battlefield—seven dead scorpions, their bodies already attracting smaller scavengers. Waste not, apparently, was the motto of the Carboniferous ecosystem. The bone spear was kind of destroyed. But the scorpions... Their tails.
The stingers were each the length of his forearm, curved like sickles, wickedly sharp. He spent the morning harvesting. It should have been disgusting. Was disgusting. But disgust was another luxury he couldn't afford.
By noon, he had three new weapons: two stingers bound to wooden handles with strips of his increasingly tattered lab coat, forming short spears. The third he left free, a dagger of sorts.
Better armed than yesterday. Slightly safer than the day before. It would have to be enough.
The shelter needed repairs. Half the roof had been torn away during the fight. The wooden supports had cracked. Sekitanki set to work mechanically, gathering, building, improving.
His mind drifted as his hands worked—back to Tokyo, to his lab, to the life that felt increasingly like a dream someone else had lived. Dr. Yamamoto had probably declared him dead by now. There'd be a memorial service. His parents would cry. Colleagues would say respectful things about his contributions to science. And in a year, maybe less, everyone would forget.
That thought should hurt. It didn't though. Maybe that made him a monster. Or maybe he'd been empty so long that losing the world didn't feel like losing anything.
But staying alive—moment by moment, fight by fight—that felt like something. Purpose measured in heartbeats. Meaning found in the space between breathing in and breathing out.
He rebuilt the shelter as the afternoon faded. Made it stronger. Made it safer. Made it home. When night fell again, Sekitanki sat at the entrance with his new weapons arranged around him, watching the forest come alive with predators.
They'd come for him eventually. Something bigger, meaner, smarter. And maybe that thing would kill him. But not tonight. Tonight, he was alive. And for the first time in years, that felt like enough.
TO BE CONTINUED... [NEXT EPISODE: "Arthropleura: The Walking Wall"]