Glowing marks stretched along the tunnel, as if sharp fingers had left their imprint on the walls, lines that pulsed with a sickly green light. Luca only noticed them when he stopped. When he could no longer hear the whispers that seemed to crawl along the walls or the dripping. The damn dripping.

  He gripped his knees, bending over as his labored breathing echoed in the confined space. It’s okay, he told himself, though each inhale still felt like he was sucking air through a dust-filled filter. It’s okay.

  Recovering slowly, he straightened up and looked around. He was at a ‘T’ intersection. Another tunnel continued to the left, marked by a mini-sun carved at the top—a design he’d seen before—while a large black puddle lay on the other side, still but damp. The sight of it was enough to make his nose react, bringing earthy, damp notes to his brain, overlaid by a sharp tang.

  The smell calmed him, to some extent. Even if it meant he was in more danger than before, the mud pools were certainly an indication that he was on the right path. He was closer to completing his mission.

  He was sure the four-hour mark hadn’t passed—maybe two? Two and a half?—but he preferred not to think about it too much. Trying not to curse himself was harder than it seemed.

  Luca continued down the tunnel, part of him relieved by the absolute silence that now enveloped him. Only his footsteps sounded faintly, a hollow tapping that echoed as if he were walking inside an empty wooden box, while the glowing marks on the walls helped him move without stumbling. The space was now wider, easily three times the width of the first tunnel, as if it had been made to let something of that size through, or several at once. What a thrill.

  At least he didn’t feel claustrophobic anymore. Not as much.

  When he reached the next tunnel, marked by a familiar red-tinted carving, he was met with a surprise. The amount of light—no, the amount of what emitted light—was greater. Much greater. It was as if someone had dumped a bucket of phosphorescent paint everywhere. The glow reverberated off every wet surface. The smell, as expected, was unbearable, a direct assault on his poor nose.

  Resigning himself to losing his sense of smell for that Mystery, Luca paid close attention to the ground. It was harder to avoid stepping in the puddles due to their sheer number, but this time he had no intention of losing his shoes.

  The echo of voices reached his ears, breaking the silence.

  “—Over there.”

  It was familiar.

  “Wait, I hear something.”

  If they were trying to be stealthy, he hoped that wasn’t their best attempt. They sounded like amateurs playing spies.

  The voices came from his right, but there was nothing obvious there, and the path continued straight ahead. He scanned the walls, finally noticing an opening that was only visible from a certain angle, camouflaged among shadows and natural textures. There was a torch further inside, flickering with an amber light that fought against the gloom, and next to it, two familiar figures—one more than the other.

  Luca peeked in, meeting Nagato’s eyes, whose tired and distrustful gaze greeted him before he could say anything.

  “Look,” Nagato hissed at Nadeene, gesturing toward him with a sharp nod of his head.

  She returned his wave with a raised eyebrow, the mud covering her right cheek shining under the torchlight.

  Uh. Mud covered most of their hair, clothes, and skin, and both looked exhausted, as if they’d run a marathon in the middle of a mudstorm. Guessing what had happened, he gave them a sympathetic grimace.

  “What the hell, dude?” Nagato blurted out, staring—ah, his arm. His hand.

  “An accident,” Luca offered, then smiled. “Did you decide to follow my advice from the last mission?” he referred to their current appearance, which was similar to what he had looked after crawling through the dirt under the rain.

  Nadeene explained, “It’s the only way to avoid the abominations. If they found you, they kill you.”

  “And it keeps the lunatics away too,” Nagato muttered, frowning as he absentmindedly pushed a strand of hair stuck to his forehead.

  Luca nodded, already knowing that. “I found the forest’s death rule,” he offered. “The creature mimics sounds and voices, but it only attacks if you look back.” He thought of the sparse traces and the more psychological than physical presence, not to mention its cunning use of loved ones. His frown deepened. “Have you seen the others?”

  “The mines are big,” Nadeene murmured after a moment. “The forest too. They could be anywhere. But they probably spawned together, so they should be fine.”

  “She’ll be fine,” Nagato said, rolling his eyes and giving him the Look.

  Brat. Luca sighed. “Are you going to keep insisting on that?” He turned to Nadeene. “Where were you heading?”

  “Toward the crystal. But there are some complications.” She didn’t seem happy to admit it.

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  Luca pointed toward the path he’d come from. “The Chambers should be that way, I think. We should hurry before time runs out.”

  “There’s only an hour left,” Nadeene confirmed, wiping a mud stain from her arm with quick movements, revealing a watch that glowed faintly under the torchlight.

  “That’s enough time,” Nagato assured, though his tone didn’t sound as confident as his words tried to convey.

  At that exact moment, a noise sent a shiver down their spines. It was like the sound of something sharp scraping against something hard, an intermittent screech that echoed like nails on a giant chalkboard. The whispers returned. Insistent.

  “Let’s go,” Nagato demanded immediately, his eyes wide.

  Luca didn’t need any further explanation. The three of them bolted down the same path he’d taken, reappearing in the wide, well-lit tunnel.

  “What the hell…?”

  “Activity seems higher here,” Nadeene whispered, scanning their surroundings with a scrutinizing expression.

  Nagato pulled out a flashlight and turned it on, shining it on the walls. When he noticed Luca’s gaze, he shook the flashlight. “This is my curse. What did you get?”

  Luca snorted and pulled the multi-tool from his pocket, showing it off with a casual gesture.

  “Not bad,” Nagato murmured, turning his attention back to the walls. “Here’s the same figure we saw before.”

  “The abominations leave these marks on the walls,” Nadeene explained, pointing at the spirals carved—or scratched? What was the right term here?—with a dirty finger. “We’ve been following them for a while, but we haven’t found anywhere like this—”

  The echo of a long moan not only sent a sudden jolt through his head but also froze all three of them.

  “Mud,” Nadeene hissed, looking around.

  Luca pointed in the direction where he knew there was a pool, and the three of them quickly slid toward it, the noise nipping at their heels.

  When they reached the still pool in record time, the two experienced ones immediately submerged without hesitation, sinking like stones. In less than a blink, he couldn’t see either of them.

  Luca stopped at the edge with a grimace.

  He… didn’t know how to swim. He didn’t even know how to float.

  Not in water, and certainly not in what looked like a denser, dirtier version of it.

  The moan echoed again, louder, closer. This time, it was accompanied by a wet crunch, like the sound of something large dragging itself toward them.

  His skin prickled, but his expression grew determined despite the pain. The sound wasn’t coming from the direction they’d run from, but the opposite. He gave one last look at the two, then turned on his heel and retraced his steps. He crossed through the passage where he’d found Nagato and Nadeene and reached the end of the wide tunnel, taking the turn.

  The space was narrower, and it was almost impossible to walk without stepping on the ‘acid’ on the ground. As if that weren’t enough, there was more of it on the ceiling, dripping onto the floor. But Luca didn’t have time to think about the risks of being burn. And he had no other options. He pushed forward, tiptoeing between the puddles, shoulders pressed together to make himself as thin as possible.

  Luca didn’t know how he made it to the end, but he did.

  There was a new tunnel, though something about it told him that it was different than the previous ones. The glowing marks that had once seemed like messy scribbles were now arranged more orderly, in straight lines parallel to the ground, as if someone had carefully traced them with an invisible ruler. Their glow was more constant, casting a greenish light that bathed everything. It looked like a ghostly place.

  At the end, illuminated by that strange clarity, was a rusted but intact metal door, with thick rivets that seemed designed to withstand anything—and a thick, twisted chain hanging, half already consumed by the acidic substance. Traces of the old mine were also present: an overturned mining cart, half-melted, tucked into an abandoned corner, with twisted pieces of a haulage track scattered around.

  Luca could barely smell anything anymore, considering his nose had numbed from the strong odor of burnt wood and metal that had followed him the entire way. But here—here he could smell something new. Something he couldn’t explain.

  Approaching the door with caution, he pulled the multi-tool from his pocket. The tool glinted faintly under the greenish light of the walls as he began to work. Having already some experience with this, it didn’t take long for him to analyze the mechanism and mentally figure out how to open it. The good news was that it wouldn’t take much effort; the bad news was that he had less time than he thought, judging by the terrifying sound bouncing through the tunnels, coming toward him like a painful cacophony.

  His sweaty hands struggled to open the door as quickly as possible, acutely aware—very aware—that they could be there at any moment. The ‘abominations,’ as Nadeene called them. A fitting name. His mind conjured blurry images of twisted forms and sharp claws that he tried to push away. There was no way he’d fall for those cheap tricks. There was no time for that.

  With a click, the door finally unlocked, creaking loudly enough to attract every nearby creature. Cursing inwardly, Luca abandoned all pretense of stealth and lunged to the other side, slamming it shut behind him with a sharp thud that echoed harshly in the momentary silence.

  Immediately, a message appeared in front of him, floating as if projected in the air:

  How lovely. It didn’t say “survive,” but it practically meant the same thing.

  This must be part of the ship now, he thought, observing his surroundings with a mix of awe and caution. The side he’d ended up on was different from what he’d expected. A hallway stretched in both directions, perfectly straight and symmetrical. The walls were square panels of whitish metal, crisscrossed by thick, glowing red lines that seemed to pulse softly, like bloody veins. The floor was made of the same material, with fainter scarlet lines.

  The sound of the door being scraped from the other side set him in motion.

  He picked a direction at random, aware that he’d end up in the same place anyway. The most important thing right now was to find the Core—and for that, reaching the Energy Chamber was crucial.

  His thoughts went to his coworkers for a moment, but —he believed they would be fine.

  Anyone who could not save themselves had no place delving in the Mysteries.