Gabriel remained curled inside the shell for a long while, motionless, until the surrounding currents finally returned to stillness. The shell, an ancient spiral remnant of a long-dead mollusk, groaned faintly in the shifting pressure. Its calcified walls were cool against his skin, encrusted with barnacles that pulsed gently with the tide. Shadows slithered beyond the shell’s mouth, flickering like the ghostly arms of forgotten predators.

  Only when the distant darkness grew calm again did he begin to stir. He moved slowly, every limb heavy, deliberate. His fingers—longer now, the joints subtly restructured—pressed against the inner wall for support. He drew a deep breath through his gills—yes, they had become gills now, slits on his neck filtering water with surprising efficiency—and exhaled, releasing a string of bubbles that drifted upward like tiny glass bells, swallowed quickly by the abyss.

  The wound on his arm still ached dully, but no longer throbbed with acute pain. A translucent film covered the gash, thick as if spun from some organic resin. It flexed slightly when he moved, supple yet firm, like a second skin. He ran his fingers over it—cool, almost rubbery—and felt a strange satisfaction. His body was adapting. Rapidly.

  But adaptation demanded more than healing. It needed energy.

  “Energy exchange,” he murmured into the water, voice lost to the silence. “Every living system begins with it.”

  The words belonged to his old ecology professor, an aging biologist with salt-and-pepper hair who had once held an auditorium captive with nothing but a chalkboard and the quiet, steady cadence of truth. Gabriel could almost hear the man now, as though the sea had stolen his voice and played it back in distorted echoes.

  He slid out from the shell’s mouth, carefully scanning his surroundings. The seafloor was a jagged tapestry of basalt ridges and silt-choked crevices. Visibility was low, lit only by the faint, ambient glow of bioluminescent algae smeared across the stone like spilled paint. Tiny organisms drifted in the water, blinking in and out like stars.

  Each movement Gabriel made was cautious, fluid. He had learned—painfully—that sudden motions could draw the attention of things better left unnoticed. His body moved more naturally now, aligning itself with the flow of the currents. His muscles no longer resisted the crushing weight of the deep; instead, they worked with it. He no longer felt like a foreign body in an alien sea. He moved like he belonged.

  His eyes, now sensitive to the barest fluctuations in light, caught a glimmer behind a rocky outcrop. He angled toward it, gliding low, keeping to the seafloor. As he drew closer, the glimmer resolved into a colony of pale, elegant tubes anchored to the stone like a garden of bone-white fingers. At their tips, translucent filaments waved gently, tasting the water.

  He recognized them—or at least, their Earthly analogues. Tube worms. Riftia pachyptila.

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  “No mouths, no digestive systems… they rely on chemosynthetic bacteria,” he thought. “Which means—there’s geothermal activity nearby.”

  The realization made his pulse quicken. He pressed his palm to the rock near the worms and felt a subtle warmth radiating through the stone. Not heat like fire, but a mineral heat, soft and constant. A hydrothermal vent must be close. An entire ecosystem, born not of sunlight, but of chemical reaction, thrived here.

  A gust of movement above made him freeze. He looked up sharply, muscles tensing, and waited—only a cloud of silt, stirred by something large moving far overhead. He exhaled slowly, a silent stream of bubbles winding upward.

  Focus.

  He turned back to the worms, singling out the largest. It swayed rhythmically, a slow and hypnotic motion. With a sudden thrust, he darted forward, fingers closing tightly around the base of its tube. The worm struggled as he pulled—it resisted, like tearing a rooted plant from the earth—but with a final wrench, it came free.

  It writhed in his grip, its luminous body pulsing faintly, casting rippling shadows on his altered skin. His stomach clenched, both in hunger and revulsion. But instinct overruled hesitation. He tore off a piece and bit into it.

  The texture was alien—gelatinous yet fibrous, and the flavor burned with a metallic sting, sharp with sulfur and iron. His mouth instinctively rebelled, but he forced himself to chew, then swallow.

  Warmth. Not from the worm’s body, but from within. A surge of energy radiated outward from his core, igniting dormant systems in his body. His limbs tingled. His vision sharpened. He gasped as if surfacing from deep water.

  He had consumed something vital—something foundational.

  He quickly tore off two more worms, tucking them into a crevice in the rock, anchoring them for later. He crouched there for a moment, breathing slow and steady, heart thudding with new rhythm. The faint pressure in his ears was gone, replaced by an odd sense of balance, as if his inner structure had recalibrated.

  He turned his gaze downward and noticed movement—small, insect-like creatures skittering between the cracks. Silvery-blue, armored, with twitching antennae and segmented limbs. Primitive arthropods, perhaps analogous to Earth’s deep-sea isopods.

  So the food chain here wasn’t singular. It had depth, structure. Even in this abyssal wasteland, life built upon life.

  And unlike the sunlit ecosystems of Earth, this one owed nothing to the sky.

  It was life driven by pressure, heat, and relentless will.

  He leaned against the rock, eyes scanning the terrain. The light from the worms barely illuminated a few meters in any direction, but within that radius, an entire world moved—unseen yet methodical. Every creature here was a survivor, a product of brutal selection.

  Even himself.

  His reflection flickered in a smooth patch of stone. He studied it. His features were still his, but subtly altered. Sharper cheekbones. Slightly elongated pupils. Gills fluttering like petals beneath his jaw. Veins beneath his skin shimmered faintly with bio-luminescent blue.

  “Am I still human?”

  The thought came quietly, not with fear, but with curiosity.

  If evolution was nature’s way of sculpting resilience, then what he was becoming was simply the next version—something carved by necessity, not design.

  A deep rumble vibrated through the stone beneath him. Somewhere nearby, the vent expelled another plume of mineral-rich water. Tiny creatures darted in to feed.

  He crouched low again, hand resting on the rock’s warm pulse, and watched.

  The ecosystem moved around him in perfect silence. No drama. No spectacle. Just survival. Refined. Constant. Absolute.

  And he was no longer a stranger to it.

  He was becoming one of its own.