The rails beneath Erevos hummed softly, a low, steady vibration that cut through the heavy silence of the burned forest. Karl's visor flickered with the residual nanite mapping, the faint overlay of thermal readings illuminating the blackened trunks and scattered debris around them. The remnants of the storm had passed, leaving only scorched earth and the acrid scent of purified Ichor lingering in the air.
Yet something felt… off.
He had traversed countless ruins, fought innumerable threats, but the energy rippling through this place wasn't like the ordinary Ichor pockets or rogue nanite aberrations. It pulsed with an intelligence, a conscious weight, something that pressed against the edges of his perception. Karl's hand hovered near the Drive Regulator, fingers brushing the metallic housing of the cockpit.
"…Agnes," he murmured, voice calm but taut, "…do you read this? There's something… wrong here."
Agnes's avatar appeared beside him, a shimmer of her usual teasing edge softened into a quiet focus. Her eyes scanned the heat maps and energy readings, flickering as if parsing layers of code and energy simultaneously.
"Yeah…" she said, tone low. "…This isn't just residual storm energy. Something… alive is burning inside this forest. I'd call it… extremely hostile."
Karl's lips twitched into a faint smirk, though his eyes were sharp, scanning the horizon. "…Hostile, huh? You say that like we haven't already handled worse."
Agnes gave him a sidelong glance, her half-smile tinged with unease. "…Not like this. There's… purpose behind it. Intelligence. I'd wager it's a Core Bearer."
The words landed like a weight in Karl's chest. His mind immediately flashed back to Goliath, the first Core Bearer he had faced. The memory wasn't gentle. Every near-death moment, every explosion, every strike that should have ended him—hadn't. Three times he had come close to total annihilation, his body rebuilt by Yggdrasil's bond, each failure searing lessons into his mind. By the end, he had ascended through near-death tenfold, bruised, burned, and barely whole.
"…A Core bearer?" he echoed, jaw tightening slightly. "I should have known. Nothing else carries this… weight. I've felt it before. And I… survived it once. Barely."
Agnes's gaze softened, though her avatar remained firm. "…Then you know exactly what this means, Karl. This one isn't a mindless threat. It's going to test you—just like Goliath did."
Karl exhaled, letting the memory wash over him. Every shattered limb, every searing flame, every disorienting strike from Goliath replayed in his mind, but he suppressed the fear, letting only the lessons remain. "…I know," he said quietly. "…I won't… I can't underestimate it. Not again."
The forest ahead shivered under the subtle tremors of heatwaves, faint streaks of royal azure light barely visible in the swirling ash. At first, they were nothing more than flickers—an optical illusion of the wind. But then Karl saw it: a tornado of deep blue flame, rolling and twisting, bending reality around its axis. It wasn't fire as he knew it. It moved with intent, compressing, expanding, and folding space within itself.
"…Agnes," he whispered, leaning forward slightly, "…that's no natural phenomenon."
Her avatar's eyes narrowed. "…I concur. That… that's a manifestation of a Core Bearer's energy. Look closely."
Through the visor, Karl could just make out the mechanical silhouette inside the swirling inferno. It was vast, towering, and clearly sentient. Armor segments shifted like plates of molten metal, vents pulsating in rhythm with the flames. The chest cavity glowed faint sapphire, barely perceptible beneath the twisting energy. Even from this distance, Karl could feel the pressure of its presence—a living furnace wrapped in cold logic and merciless design.
"…Sentinel," he muttered, the word tasting like a warning on his tongue. "…It's… massive."
Agnes floated closer, her tone now carrying a quiet edge of admiration and caution. "…That's not just a Core Demon. That's a Pyroclast Sentinel. Rare, high-tier. Its core… if you can even reach it, will be the key to surviving this encounter."
Karl's mind raced, recalling the lessons Goliath had taught him. Direct strikes would be ineffective; the body would regenerate. He had to find the core, time his assault precisely, and exploit every environmental advantage. The Sentinel's flamethrower arms could melt steel, its heatwaves distorted the air, and the swirling flames of its internal vortex made targeting nearly impossible. Even the slightest miscalculation could burn him alive, the nanites inside him cooking from sheer heat.
"…I'm not Goliath," he muttered to himself, jaw tightening. "…But I've survived once… I can do it again."
Agnes's voice softened in response, almost like a caress through the visor's auditory feed. "…Karl… just… promise me you won't repeat the near-death… three times this round."
Karl allowed himself a brief, wry smile. "…I'll try."
Even as he spoke, the Sentinel shifted. The vortex of royal azure flames grew, its rotation intensifying, sending shockwaves through the nearby trees. The inferno was no longer subtle—it roared like a living beast, twisting branches into molten shapes before collapsing them into the ground. The sheer heat made Karl's visor lenses fog slightly, and he could see the nanites reacting, attempting to maintain a buffer between him and the extreme environment.
"…It's aware of us," Agnes observed, her voice tense. "…It's studying the rails. Calculating trajectories. Every movement you make, it's preparing to counter."
Karl leaned back, eyes narrowing. "…Good. Then it'll see the first strike coming."
He scanned the swirling inferno, tracing faint points where armor segments overlapped, noting where the sapphire glow of the chest orb flickered through. The Core… that's where he had to hit. Not the arms, not the legs—those were distractions. Everything else was just a shell. He clenched his gauntleted fists, the Drive Regulator humming softly in response, almost as if it sensed his focus.
"…Ready when you are," Agnes murmured, voice steady, betraying only the faintest tremor of excitement. "…Just… don't die before I can watch the fireworks."
Karl let a small smirk tug at his lips. "…I wasn't planning to. This time."
The Sentinel twisted slightly inside the vortex of flames, its sapphire chest orb glowing a little brighter, as if acknowledging his presence. The forest around them seemed to hold its breath, ash suspended in the humid heat, the rails beneath Erevos vibrating with anticipation.
And Karl knew—this wasn't just a fight. It was a test of every near-death lesson he had learned, every nanite trick, every ounce of skill and instinct honed through survival.
The first strike hadn't come yet. But the storm of royal azure flames promised it was coming—and Karl's pulse quickened, not with fear, but with the cold thrill of battle.
The Sentinel loomed within its inferno, fully formed, fully aware, and utterly relentless.
Karl tightened his grip. "…Let's see if I survive this time..."