Matthew did not immediately offer his judgment. Instead, he handed the bronze fragment to Alvin.
“Recognize it?”
Alvin took it and examined it carefully for a moment before slowly shaking his head. “I don't recognize the writing. But the material...”
He tapped the fragment lightly with a finger, producing a dull metallic clink. “It matches the bell suspension loop found in the North District.”
Matthew felt a sudden stir in his mind. Another bell. It seemed the bronze artifacts in these ruins truly originated from the same system.
Violet had previously translated that badge: Underground Clock Tower, Seventh Storage Room. And now, a bronze fragment engraved with “Seven” had appeared. This was by no means a coincidence.
Matthew's gaze slowly swept across the hall—the stone pillars, the walls, the floor—before finally settling on the far side of the room.
There were seven archways, each identical in style, though some had collapsed while others remained intact. Due to the dim light earlier, no one had counted them carefully. But looking closely now, there were exactly seven.
“Investigate,” Alvin ordered in a low voice. “Stay together.”
The two Gold Rank combatants took up guard positions while the rest began checking the hall. Matthew walked slowly along the wall, keeping his Spirit spread at minimum output—not to search, but to serve as an early warning system. That way, he wouldn't leave obvious traces of spellcasting while still sensing danger in advance.
The first archway was blocked by fallen rocks. The second led to a collapsed corridor. The ground before the third was completely fractured, making it impassable.
It was only when he reached the Fourth Archway that Matthew halted.
The dust here was noticeably thinner than elsewhere. Furthermore, there was a faint scrape mark at the corner of the wall, looking as if something heavy had been passed through here repeatedly over a long time.
He squatted down and lightly brushed his fingertips over the ground. Beneath the dust layer, a shallow groove was revealed, about half a foot wide, curving deep into the corridor. It didn't look like wheel tracks, nor did it resemble a wooden crate. It looked more like... the trace left behind by a heavy, round metal object rolling across the floor.
Matthew did not voice his speculation, merely keeping it to himself.
Just then, a voice suddenly called out from the back of the team.
“Investigator!”
Everyone immediately turned around. A Silver Rank Class holder stood in the center of the hall, looking somewhat confused. “Is... someone missing here?”
The air instantly fell dead silent.
Alvin's gaze darkened. “Count off.”
“One.”
“Two.”
“Three.”
Everyone responded in turn. Soon, the result was clear: they were short one person.
When they entered the ruins, there had been eight of them. Now... there were only seven.
What was even stranger was that no one knew who had vanished.
Ryan frowned. “Weren't we all here just a moment ago?”
The other Gold Rank combatant immediately denied it. “No. I remember there only ever being seven of us. Wait...” Halfway through speaking, his expression suddenly froze. He realized that he couldn't recall the face of the eighth person. He couldn't even remember the name.
Silence gripped the hall as an indescribable chill slowly spread.
Matthew's heart jolted. This wasn't a standard disappearance. Their perceptions were being altered.
He immediately closed his eyes. Inside his spiritual sea, his Tier 2 Wizard spiritual core slowly turned, sending a wave of coolness rapidly through his consciousness. Almost simultaneously, a blurred memory re-emerged.
The eighth person was a young Silver Rank Class holder who had helped adjust someone else's safety rope before they entered the ruins. But now, aside from Matthew, no one seemed able to recall his existence.
Matthew slowly opened his eyes, choosing not to speak right away. He had suddenly realized an even more terrifying question: If he told everyone now, “We are missing a person,” would they immediately forget him too?
Matthew stayed silent, lightly rubbing his temples. The memory he had just recovered was already starting to blur again, like words written in the sand being gradually scattered by the wind.
He realized instantly that the effect was ongoing. It wasn't a single occurrence, but a slow erosion of everyone's cognition.
Alvin had also sensed the anomaly. His eyes swept over everyone as he said slowly, “Everyone, stay where you are and don't move. Recount everything that happened after entering the ruins in chronological order.”
No one raised an objection. This was the most basic method for investigators. When memories drifted, cross-verification was often far more reliable than individual recall.
The first Class holder began explaining—from entering the rift valley to riding the lift platform and reaching the hall. There were no issues with his account.
The second person, then the third, gave essentially the same story.
Until Ryan spoke. Halfway through, he suddenly stopped, his brow knotting tighter and tighter. “Wait. I remember... someone stepped on my foot while we were on the lift.”
He instinctively looked down at his boot. Sure enough, half a clear muddy footprint remained on the leather. Yet no matter how hard he tried, he couldn't remember who had stepped on him.
Matthew slowly squatted down and carefully examined the print. The sole pattern differed from everyone else's boots present.
In other words, this footprint belonged to the person who had already been forgotten.
The physical evidence remained, yet the person was almost wiped from memory.
Alvin walked over as well, his expression turning solemn for the first time as he looked at the footprint. Without a word, he retrieved a palm-sized leather ledger from his belt and quickly flipped to the first page, which contained the registered names recorded before entering the ruins.
The next moment, his movement froze.
The final line of the list was completely blank. It hadn't been torn out, nor was it smudged with ink. The spot where a name had once been written now held nothing, as though it had never been written at all.
Alvin slowly closed the notebook and took a deep breath. “It isn't that our memories are playing tricks on us. The records... have been affected as well.”
As soon as those words were uttered, the atmosphere in the hall grew suffocatingly heavy. If even written words could change, what else could they trust?
While everyone was silent, Matthew suddenly remembered something. Before entering the ruins, he had kept the habit of recording daily investigation notes. Before setting out today, he had written a page that included the number of participants in the operation. That notebook was in his pack right now.
Without making a sound, he pretended to adjust his gear while quietly opening the notebook.
The page was still there, and the ink hadn't changed. Written clearly at the top was:
Participants: Eight.
Below it, however, only seven names remained. In the eighth spot was merely half of an incomplete stroke, looking as if someone had just used an eraser, or as if the writing were slowly fading away.
Matthew stared quietly without closing the notebook. A terrifying speculation suddenly crossed his mind.
Perhaps what the ruins were affecting wasn't memory, but—
Existence itself.
If this erosion continued, what ultimately vanished wouldn't just be names.
“Don't move.”
Alvin's voice was very soft, yet it brought everyone to a dead halt.
He, too, had spotted the black line—or more accurately, he noticed that when the lantern light cast over it, a small segment of light seemed to be missing, as if the glow were being swallowed upon hitting that area.
Alvin didn't order them forward. Instead, he squatted down, picked up a fingernail-sized pebble from the ground, and tossed it gently over.
The pebble arced through the air and crossed the black line.
Clack.
It landed crisply on the other side. No mechanisms triggered, no explosions occurred, and no anomalies followed.
Yet no one relaxed, because the stone had vanished.
It hadn't shattered, nor had it rolled into the shadows. Right under everyone's gaze after landing, it gradually turned transparent until it was completely unseen.
Dead silence fell over the hall.
A Silver Rank Class holder couldn't help swallowing hard. “Is it... an illusion?”
No one answered.
Alvin picked up a second stone, throwing it with greater force this time. The pebble crossed the black line and struck the wall with a clear clatter before bouncing back and rolling near the line.
The instant it rolled back across the black line, the stone reappeared in everyone's field of vision, tumbling all the way back to Alvin's feet.
Alvin bent down, picked it up, and examined it closely. There was no change in weight and no damage to its surface.
He slowly let out a breath. “It didn't vanish. It's...” He paused, as if searching for the most precise description. “Unseeable.”
Matthew understood immediately. It wasn't that the stone ceased to exist; rather, once it crossed the black line, they could no longer observe it.
Matthew slowly closed his eyes. His Spirit spread outward like ripples on water, gradually crossing the black line.
In the next instant, his spiritual perception unexpectedly remained uninterrupted. Beyond the black line lay the same straight stone corridor, except the air had grown unnaturally heavy, accompanied by a faint... low-frequency vibration. It was as though, far in the distance, some colossal entity was slowly breathing.
Matthew immediately withdrew his Spirit, a thin layer of sweat breaking out on his forehead. The vibration hadn't attacked him, but it had caused ripples in his spiritual sea.
This proved that beyond the black line, a special area truly existed.
“Find anything?” Alvin asked suddenly.
Matthew was silent for a moment before choosing to share part of it. “The air is different. It feels like entering a different environment.”
Alvin nodded; this matched his own assessment. He didn't pry further, simply pulling a coil of thin rope from his backpack. He secured one end of the rope around a stone pillar and tossed the other end across the black line.
The rope didn't snap, nor did it disappear. It lay there quietly. He gave it a gentle tug, and normal resistance came from the other end.
Alvin stood up and looked around at everyone. “Record the first rule.”
An investigator immediately took out his notebook and wrote quickly.
Alvin said slowly, “Rule One: An observation boundary exists behind the Fourth Archway. Objects crossing the boundary do not vanish, but leave the line of sight. Currently, no damage to non-living objects has been observed.”
The clerk finished writing and nodded slightly.
Just then, Matthew suddenly spoke. “Wait.”
Everyone looked at him.
Matthew stared at the rope spanning the black line and said slowly, “There is still one final verification needed.”
Alvin raised an eyebrow. “What?”
Matthew walked to the rope, knelt down, and used his dagger to lightly sever a small strand of fiber from the section of rope on this side of the black line.
Then, he gestured for everyone to observe.
The rope remained taut. But in the next second, on the other side of the black line, the outline of the previously invisible rope unexpectedly... surfaced for a split second.
Though it lasted less than half a second, it was enough for everyone to see clearly.
On the other side was not an empty stone corridor. Standing silently in the center of the passage was an ancient bronze bell three times the height of a man.
No one in the hall spoke. Everyone's eyes fell upon a line of ancient writing that was slowly glowing.
The light wasn't harsh; rather, it was quite gentle, as if someone had just lit a lamp that had been asleep for centuries.
Alvin didn't draw near, merely turning to look at Matthew. “Can you recognize it?”
Matthew was silent for a moment before saying slowly, “Only part of it. The general meaning is...” He looked at the glowing glyphs and said word for word, “'Do not enter if the bell does not toll.'”
Alvin slowly nodded without prying or questioning. He knew Matthew had been studying the Ancient Kingdom Tongue recently, so recognizing a few words wasn't surprising. What truly caught his attention was the phrasing.
Do not enter.
Not “Intruders shall die,” nor “Violators shall be executed,” but a statement that sounded almost like advice.
A Gold Rank knight whispered, “If this is a warning, it means there is definitely danger inside.”
Ryan frowned. “But who left it? Someone from the First Royal Capital?”
No one could answer, for history six hundred years ago had long been shattered into fragments.
Matthew's gaze fell back onto the line of ancient script. At the end of the glowing glyphs, he noticed an extremely shallow carving. It wasn't left behind later, but had been engraved together with the entire line of text, like a signature.
He took a slow step closer. By the light of the lantern, he finally made out the last few characters:
—Bellkeeper Arian.
Not an organization, nor a family, but an individual's name.
Matthew felt a subtle shock in his heart. If this was a signature, it meant the person who left the warning wasn't a ruler standing high above, but... the person responsible for guarding this place.
Alvin also noticed the carving. “A name?”
Matthew nodded. “Most likely.”
Alvin pondered for a moment, then retrieved paper and pen to solemnly write down the name. An investigator's instinct told him that any specific personal name could prove to be the key to unlocking the secrets of the ruins.
The moment he finished recording it, that extremely faint vibration echoed once more from deep within the hall.
Hum...
This time, the sound lasted longer. Immediately following it, an almost imperceptible draft blew out from deep within the Fourth Archway.
The wind was cold, yet it bore no smell of decay. Instead, it carried a faint... hint of floral fragrance.
Everyone's expressions grew complex. How could there be floral fragrance in ruins six hundred years deep underground?
Matthew, however, suddenly realized another detail: the air was moving.
This meant that beyond the Fourth Archway was not an enclosed space. There was... still a path leading deeper.