Cold sand pressed against her cheek.

  Suzume's eyes snapped open to darkness so complete she thought she might still be unconscious. Her lungs burned with each breath, the taste of mineral-heavy water coating her throat. She pushed herself up on shaking arms and immediately regretted it. Pain shot through her ribs like someone had taken a baseball bat to them.

  [Status.]

  The blue light from the System interface cut through the darkness.

  HP: 23/70

  That explained the everything-hurts feeling. Her MP sat at 85/105, which meant she'd been out long enough for some regeneration.

  She dismissed the window and let her eyes adjust. Not total darkness after all.

  Somewhere far above, patches of bioluminescent moss gave off just enough light to make out shapes. She was lying on a beach of black sand that stretched maybe ten meters before hitting water. The pond—lake?—extended beyond what she could see, its surface mirror-smooth and reflecting the faint green glow from above.

  [Check for threats first. Feel sorry for yourself later.]

  She stayed still, listening.

  Water lapped gently at the shore. Somewhere in the distance, she could hear dripping. No growls. No footsteps. No chittering of a hundred teeth. Just her own ragged breathing and the sound of an underground lake that had no business existing this deep in a C-rank dungeon.

  Her gear was soaked through. The tactical pants clung to her legs like they were trying to become part of her skin. Her boots squelched when she finally stood, sending fresh waves of pain through her torso. Probably bruised ribs. Maybe cracked. The first aid kit had survived the fall, sealed in its waterproof case.

  The bodycam hung from its mount, the lens cracked straight down the middle.

  She pressed the power button. Nothing. Pressed it again, holding it longer this time. Still nothing. Water had gotten inside, probably fried the circuits. The modulator was in the same state—dead weight in her pocket.

  [Yumi saw me fall. Saw the screen go black.]

  Her friend was probably losing her mind right now. Calling everyone she knew, trying to get someone to mount a rescue. But who would come? The Player Response Officers wouldn't enter an unstable dungeon. The association would wait for it to stabilize, which could take days or weeks.

  [Or never.]

  Some dungeons never stabilized. They just sat there, reality broken, until the System decided to close them entirely. Portal collapse. Everything inside—monsters, treasure, bodies—gone like it never existed.

  Suzume pulled up her skill list. Emergency Treatment would put her at 53 HP. Enough to not feel like death warmed over. She activated the skill.

  Warmth spread from her core outward, like drinking hot chocolate after coming in from the snow. The pain in her ribs dulled to a manageable ache. Her breathing came easier. The skill couldn't fix everything right away, but it bought her time.

  [Now what?]

  She turned in a slow circle, taking in her surroundings.

  The cavern was massive, probably three hundred meters across. The ceiling disappeared into darkness even with the moss providing ambient light. Behind her, a sheer cliff face rose up at least fifty meters. No handholds she could see. No convenient path back up to where she'd fallen from.

  The only way out was forward, which meant either following the beach or going into the water.

  [Yeah, not swimming in the murder lake, thanks.]

  She started walking along the shoreline. Her boots left deep impressions in the black sand. After about fifty meters, she found something that made her stop.

  Ensure your favorite authors get the support they deserve. Read this novel on Royal Road.

  Bones.

  A human skeleton, still partially wrapped in the remains of Player gear. The metal clasps and buckles had survived whatever ate the leather and fabric. A sword lay nearby, the blade corroded but intact. She checked for a guild insignia on the remaining equipment but found nothing identifiable.

  [How long have you been down here?]

  She kept walking. More bones appeared—some human, most not. Monster skeletons she couldn't identify. Things with too many limbs or skulls that bent at weird angles. One looked like a spider the size of a compact car.

  The beach curved around, following the lake's edge. After another hundred meters, she found something more recent. A backpack, modern design, probably from the last year or two. She opened it carefully. Inside: protein bars (expired but probably still edible), a water bottle (empty), a lighter (fuel mostly gone), and a journal.

  She flipped through the pages. Most were water-damaged beyond reading, but a few entries survived:

  Day 3: The others are dead. Jin tried to swim across. Something pulled him under. We never saw what.

  Day 5: Found a tunnel leading up. Collapsed when I was halfway through. Lucky I didn't die. Or maybe unlucky.

  Day 8: The things in the water are getting bolder. They come onto the beach at night. I've been sleeping in the walls, finding cracks to wedge myself into.

  Day 11: I can hear them singing sometimes. Under the water. It's beautiful.

  The entries stopped there. No body nearby, which meant they either escaped or ended up in the lake.

  [At least eleven days. This person survived down here for at least eleven days.]

  She looked around.

  [Is this... is this part of the base dungeon?]

  It had to be. The dungeon destabilization would have done away with these bodies and objects at some point, in all its shifting and changing. So, it was likely the room she fell through and this space here was all part of the normal, C-Rank dungeon.

  And this person had survived eleven days inside it after falling through the same trap Suzume had fallen through.

  Which meant it was possible. Difficult, probably horrible, but possible.

  She pocketed the protein bars and lighter. Every resource counted now. The journal she left—if someone found her body, maybe they'd appreciate any warnings she could give.

  The beach ended at a rock formation that jutted into the lake. She'd have to climb over or go around through the shallows. Neither option appealed to her, but wet feet beat whatever lived in the deeper water.

  She stepped into the lake.

  The water was warm. Not hot spring warm, but noticeably warmer than the air. It came up to her ankles, then her shins as she navigated around the rocks. Nothing grabbed her. Nothing sang. Just the sound of her own movement disturbing the surface.

  On the other side, the beach continued but narrower. The cliff face had openings now—caves or tunnels leading deeper into the rock. Most were at ground level. A few sat higher up, requiring climbing to reach.

  [Escape Route.]

  She activated the skill. Golden threads appeared in her vision, but they flickered and sparked like a broken connection. The threads pointed toward one of the ground-level caves, then shifted to point at the water, then back to the cave, then up toward a higher opening.

  [Great. Even my skill doesn't know how to get out of here.]

  It felt like the System was confused. Although this place was part of the original dungeon, the destabilization had probably scrambled the dungeon's layout so badly that there might not be a clear path to safety anymore. Or there might be multiple paths, all equally dangerous.

  She deactivated the skill.

  The smart move was to rest, get her HP back to full, dry out her equipment. But staying still felt like giving up. Like accepting she was going to die down here with the other skeletons.

  [Akane lasted ten days in even worse conditions.]

  Her sister hadn't had healing skills or System assistance. Just determination and the will to see her family again. Suzume had more advantages. She had to make them count.

  A sound echoed across the water. Not quite a splash. More like something large shifting beneath the surface. Ripples spread from a spot maybe thirty meters out. Then another sound, closer to shore.

  She backed away from the water's edge.

  The ripples spread wider. Something dark moved just below the surface, too distorted to make out clearly. It wasn't swimming toward her, just... circling. Like it was curious.

  Or waiting.

  [Okay. No more beach walks.]

  She looked at the cave entrances. The flickering golden thread had pointed at the leftmost one before shifting. It was as good a place to start as any. The opening stood about two meters high, wide enough that she wouldn't have to squeeze through.

  She couldn't see more than a few meters inside. The moss grew sparser here, providing barely enough light to avoid walking into walls. She pulled out one of her remaining flares. She had six left. Each one burned for about five minutes. Thirty minutes of light, if she was careful.

  [Save them. Use the moss for now.]

  She entered the cave.

  The temperature dropped immediately. Her wet clothes went from uncomfortable to actively cold. The passage sloped upward, which was good—any direction that led away from the lake was better than staying put.

  After fifty meters, the tunnel branched. Left continued up. Right stayed level but widened. She chose left.

  The sounds from the lake faded as she climbed. New sounds replaced them. Dripping water. The occasional skitter of something small fleeing from her footsteps. And something else—a rhythmic thumping, like a heartbeat, coming from somewhere deep in the rock.

  [What kind of C-rank dungeon has a heartbeat?]

  The tunnel opened into a small chamber. More bones here, but these were different. Arranged. Stacked into neat piles against the walls. Skulls separated from bodies, organized by size. Someone had been collecting them.

  Or something.

  She backed out of the chamber and took the other path.