Gabriel dragged his exhausted body, slowly swimming toward the ocean floor. His limbs still trembled, and the wound on his arm continued to seep faintly bluish blood, dispersing into the dark waters like a ghostly shimmer. He didn’t know how much longer he could last, but he knew he had to find shelter—someplace to rest, even if only briefly.

  His eyes scanned the rocky seabed, and soon, he spotted a shadow that resembled a cave. As he swam closer, he realized it was the abandoned shell of a once-massive mollusk. Time had worn it down, its surface encrusted with barnacles and corals, a remnant of a creature long gone. All that remained was a hollow, resilient shell—a forsaken fortress in the abyss.

  Dragging his injured body, Gabriel cautiously squeezed into the shell’s interior. It was darker here than the surrounding waters, yet it offered an inexplicable sense of security. Curling into a corner, he focused on steadying his breath, taking stock of his condition.

  He lowered his gaze to his wound. The gash left by the sea scorpion’s pincers lay open in the frigid water, raw and exposed. By all logic, such an injury should have quickly become infected, possibly fatal. Yet, strangely, though his blood still seeped, it did so with a slow, deliberate rhythm. He tentatively brushed his fingers over it—expecting searing pain—but instead, he felt a layer of soft, new tissue forming.

  “My body… is truly changing.”

  The thought made his heart race—only, it shouldn’t be racing. He should have been panicking, yet his pulse had slowed, steady and deep, as if syncing with the deep-sea currents. Then, another realization struck him—his breathing no longer felt strained. Before, every inhalation had felt like his lungs were being squeezed, crushed by the sheer pressure of the depths. But now, he could take in water, instinctively extracting the oxygen without the overwhelming urge to choke.

  He exhaled a tiny stream of bubbles, watching as they drifted upward, dissolving into the void.

  “When did I start adapting?”

  Time had lost its meaning. He had no idea how long he had been hiding, but he could feel it—his body was undergoing a profound transformation. His muscles no longer stiffened in the cold, the crushing pressure no longer weighed upon his joints. Stranger still, his vision had sharpened—despite the near-total darkness, he could make out the delicate patterns on distant rocks, even detect the faint movements of tiny organisms drifting in the current.

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  This wasn’t just adaptation—it was change. Changes that were being preserved because they worked.

  He thought of natural selection—how, in extreme environments, only those who adapted fast enough survived. And he, like a displaced organism thrust into a new ecosystem, was forced to evolve rapidly or perish. His shifting blood color, his skin’s newfound resilience, the way his body processed oxygen differently—these weren’t random. He was still alive, which meant, at least for now, these mutations were beneficial.

  “If I am a part of this ecosystem now… then I am just another subject of selection.”

  A disturbance in the water made him freeze, instinctively retreating into the shell’s shadow.

  In the distant blackness, a massive shape drifted into view. It dwarfed the straight-shelled nautilus he had encountered before. Its long, coiling appendages undulated in the water, each movement sending powerful ripples through the deep. Its shell was ancient and scarred, crawling with parasitic life—like a drifting ruin, indifferent and unshakable, surveying its domain.

  Gabriel held his breath, his gaze locked onto its multi-faceted eyes. The creature did not approach the shell directly but lingered for a while before slowly gliding away.

  He exhaled softly, realizing that the abyss held a far more intricate balance than he had imagined. This place was not just a graveyard of ancient life—it was a fully functional, ordered system of predation and survival.

  His mind drifted back to the sea scorpion he had encountered earlier. These creatures seemed plucked straight from the Cambrian seas, their predatory instincts honed over hundreds of millions of years. By all logic, they should have been long extinct—yet here they were, thriving. Why?

  The answer unsettled him. This world did not follow Earth’s evolutionary history. Its ecosystem had been shaped by something else. If the environment here was more extreme than Earth’s Cambrian oceans—higher pressure, colder temperatures, lower oxygen levels—then survival required even more ruthless adaptation. And these creatures had endured, evolving along a path alien to anything he knew.

  Perhaps this world was caught in an unending cycle of evolutionary refinement, where only the absolute survivors persisted.

  He would have to become one of them. Otherwise, the next time he was hunted, he might not be so lucky.

  Remaining still in the shell’s depths, Gabriel let his mind settle. His body was still changing, still adapting. He did not yet know what he was becoming—but he knew this much: he was already far more suited to this place than when he first arrived.

  The abyss continued its silent churn, and his journey had only just begun.