The two of them walked up to the heavy metal door.
Its surface was exceptionally smooth, with no visible keyhole or handle.
The only feature was a disc-shaped mechanism in the center of the door.
The disc was evenly divided into six sectors, each inlaid with a crystal of a distinct color:
Red, orange, yellow, green, blue, purple.
Below the disc, a line of ancient Common Tongue script was carved, starkly different from the goblins' crooked scrawls:
[The Order of Colors Follows the Rainbow's Light]
Lin Xiyue tilted her head, tapping her chin with a finger. "Rainbow's light? The order of a rainbow? Red, orange, yellow, green, indigo, blue, violet?"
Her delicate brows furrowed slightly.
"But there's no indigo here."
"Perhaps in the visual spectrum of some creatures, indigo and green are considered the same," Lin Qingyue mused. Her gaze wasn't fixed on the crystals but had settled on the edge of the disc.
It was covered in fresh scratches and pry marks, radiating an aura of violent, impotent rage.
The goblins left these.
"It seems this is why those green-skins couldn't open the door."
Lin Qingyue's lips curled slightly, her tone laced with amusement.
"Expecting creatures whose entire aesthetic boils down to 'shiny is good' and who struggle just to count to grasp spectral ordering... it's no wonder they failed."
She extended a finger, its tip tracing an elegant arc through the air.
Then, she touched and rotated the red, orange, yellow, green, blue, and purple sectors in sequence.
Her movements were as smooth as flowing water, without a hint of hesitation.
With each turn, the corresponding crystal brightened.
When the final purple sector clicked into place, the light from the six crystals instantly merged, converging at the disc's center to form a miniature rainbow halo.
Click—
A crisp sound of a mechanism unlocking.
The heavy metal door slid inward with the dull grinding of rock against rock.
Behind it lay a stone-paved corridor, impossibly neat.
"It was that simple?" Lin Xiyue couldn't believe her eyes. "Those goblins couldn't even solve a puzzle this easy?"
"For goblins, sorting colors is about as difficult as making them do multiplication," Lin Qingyue said calmly, retracting her staff.
"In their worldview, all sparklies fall under the category of 'good,' with no need for finer distinctions."
[Ding! Successfully solved the color puzzle that stumped the goblins. Elation gained through intellectual superiority. Elation Value +20! Host, your common sense is a superpower to goblins!]
The sisters exchanged a smile and stepped into the corridor behind the door.
The metal gate slid shut behind them, sealing away the stench and chaos of the goblin lair, along with the thirty-three corpses.
The world behind the door made the sisters, fresh from their "Perfect Stealth" infiltration, hold their breath in unison.
This... was another dimension.
Outside was a crude, primitive cave; inside was an orderly, civilized creation.
The uneven rock floor gave way to perfectly fitted gray stone slabs.
Each slab was polished to a mirror-like sheen, clearly reflecting the soft white light emanating from the walls.
The light didn't come from glowing moss, but from some kind of crystal embedded in the walls. They were arranged in an orderly fashion, their glow constant—clearly the creation of a civilization.
The air was dry and clean, carrying a faint scent of dust mixed with metal, a world apart from the damp, foul environment outside.
The corridor was wide and straight, flanked by walls of precisely cut stone and topped by a high, arched ceiling.
Simple. Sturdy. Practical.
Everything exuded a heavy aesthetic, honed by time.
It stood in absurdly stark contrast to the goblins' chaotic, haphazard "architectural aesthetic" of using whatever they could scavenge.
"This..."
Lin Xiyue's mouth hung open. She instinctively lightened her steps, afraid the mud on her boots would defile this pristine space.
"What the hell? This floor is cleaner than our living room! Did we stumble into some ancient ruins?"
Lin Qingyue crouched down, her fingertips brushing across the cold stone slabs, feeling their absolute smoothness.
She nodded.
"Possibly. Look at the precision of these stone slabs, the craftsmanship of these embedded light crystals..."
She stood up, her gaze sweeping over the deep, clean corridor ahead.
"The goblins outside must have stumbled upon this place by accident and turned the outermost natural cavern into their dormitory."
[Ding! Abnormal civilized artifact detected. "Castle Maze" quest has been updated to exploration quest "Tracing the Ruins"!]
[Quest Requirement: Explore this area and uncover the truth of the ruins.]
[Quest Reward: Elation Value and random rewards will be distributed based on exploration completion.]
[Host, it seems the goblins are just the gatekeepers here (and not very bright ones at that)?]
The two sisters suppressed their presence and advanced cautiously down the corridor, vigilant for any unexpected developments.
Occasionally, they passed tightly sealed stone doors carved with simple geometric patterns. They tried pushing, but the doors remained immovable, as if fused with the mountain itself.
After about five minutes of walking...
A rhythmic clanging sound faintly echoed from the corridor ahead.
Clink... Clang...
Clink... Clang...
It sounded like metal striking rock.
Interspersed with the noise were some low, muffled voices.
The two sisters exchanged a glance, their figures melting into the shadows along the wall, their footsteps as light as a feline's.
At the end of the corridor lay an even more expansive space, resembling a large workshop.
The sight before them made them hold their breath again.
In one corner of the hall, several stout creatures were busy at work.
Their bodies seemed molded from rock and earth, with stocky builds and arms thicker than the sisters' thighs.
They were currently wielding delicate hammers and chisels—disproportionate to their massive frames—clanging away at a giant boulder, seemingly carving something.
Their skin was deep brown or grayish-black, like weathered mountain stone. Their movements were slow but steady, imbued with a rock-solid stability.
Information flashed on their bracelets:
[Earth Spirit Craftsman Lv. 18]
[Points: 30/each]
[Traits: An ancient race born from the earth. Gentle in nature, skilled in forging and stonework. Possesses astonishing strength but moves slowly.]
[Note: Silent craftsmen, steadfast companions. Don't be fooled by their sluggish movements; they can hammer you into the ground. Of course, against such a gentle race, combat is not the only option.]
On the other side of the hall, near some crude shelters built against the wall, another group of creatures was gathered.
They were about the same height as Goblins, their skin a sickly pale color, as if it hadn't seen daylight in ages. Their eyes were enormous, glimmering faintly in the dim light.
They seemed extremely agitated, huddled together and whispering in soft, grating tones like stones rubbing against each other. They stared nervously at the working Earth Spirits, occasionally casting fearful glances toward the direction Lin Qingyue and her sister had come from.
[Cave Dweller Lv. 12]
[Points: 10/each]
[Traits: A fragile race that has long lived underground. Timid, sensitive, with some Nachtsicht and an innate talent for sensing minerals.]
[Note: Wretched creatures of the underworld, they usually cling to stronger races for protection.]
Earth Spirits and Cave Dwellers? What are they doing here?
And it looks like the Earth Spirits are working, while the Cave Dwellers seem... imprisoned? Or maybe refugees forced to stay here?
Just then, a Cave Dweller near the stone pillar where the sisters were hiding seemed to sense something.
It whipped its head around, its huge eyes locking onto the shadows in terror, and let out a short, sharp squeak
The shriek tore through the workshop's silence.
All the hammering and whispering stopped instantly.
The Earth Spirits ceased their work and slowly turned. Their stone faces showed no expression, but the eyes embedded in the rock all swiveled to look, and their grips on their hammers and chisels tightened.
The Cave Dwellers erupted into even greater commotion, scurrying like a startled nest of rats, desperately shrinking back into the depths of their shelters as they stared in terror at the sudden appearance of strangers.
An Earth Spirit that appeared to be the eldest, with the longest beard, stepped forward.
It lowered its weapon and fixed its steady eyes on the area behind the stone pillar. A deep, slow voice, with the grating texture of rock rubbing against rock, rumbled through the hall:
"Come out, strange intruders."
"The noisy Green-skins outside... did you deal with them?"
Though slow, its Common Tongue was exceptionally clear and standard.
There's no hiding now.
Lin Qingyue and Lin Xiyue exchanged a glance and stepped out from behind the pillar.
When the Earth Spirits saw that the intruders were just two young human women, they seemed to let out a collective sigh of relief. Their tense bodies relaxed slightly, but the wariness in their eyes remained.
The Cave Dwellers grew even more terrified.
Lin Qingyue remained on guard but showed no hostility. She nodded and replied to the elder Earth Spirit, "Yes. The Goblins outside won't be disturbing this place for a while."
The elder Earth Spirit studied them carefully, its gaze lingering for a moment on Lin Qingyue's pink staff, which clashed starkly with the surrounding environment.
"We thank you for driving away the noise and chaos."
"They had occupied the entrance for a long time—loud and greedy, disturbing the tranquility of the Stone Hall and cutting off our connection to the outside world."
It paused, then continued in its slow, deliberate tone, "I am Stonebeard, the guardian of this place. These," it gestured toward the Cave Dwellers behind it, "are the Wall-Nest Clan, who are temporarily sheltering here. And you... you are humans? Why have you come to this forgotten Foundation Hall?"
Lin Qingyue's mind raced.
These Earth Spirits showed no hostility and clearly despised the Goblins.
Choosing her words carefully, she offered a half-truth: "We came in search of Moonlight Moss. The Goblins outside were blocking the path, so we had to... clear them out."
"Moonlight Moss?" The Stonebeard Earth Spirit's rocky eyebrows—if you could even call them that—twitched. "That glowing moss... yes, there is some in the deeper Crystal Cluster Caverns. But that place..."
Before it could finish, an individual who looked like the Cave Dwellers' leader stumbled forward, trembling violently.
Its pale fingers twisted together nervously as it shrieked at Stonebeard in a thin, quavering voice, "S-Stonebeard Elder! Th-they... they reek of those green-skinned bandits from outside!!"
"A-and... there's a strange, terrifying floral scent! A-are they... are they in league with those bandits?!"
Lin Qingyue and Lin Xiyue: "..."
The Goblin stench was understandable, given the recent slaughter.
But that "strange, terrifying floral scent"...
Lin Qingyue's expression remained blank, her mind fixated on a single thought: That damned floral spray must be classified as a forbidden alchemical item, never to see the light of day again.
The Stonebeard Earth Spirit turned to the Cave Dweller leader, its voice still steady. "Wallclaw, calm down. They eliminated the green-skins. That is a fact. As for the smell..."
It looked back at Lin Qingyue, a barely perceptible hint of resignation crossing its rocky face.
"Perhaps it's a trace left behind by some... unique combat method?"
Lin Qingyue remained expressionless, inwardly fantasizing about hunting down the spray's manufacturer and beating them senseless.
[Ding! Your identity has been questioned by an underground race due to the lingering "suspicious fragrance," creating unexpected awkwardness and amusement. Elation Value +77! Host, the side effects of your "chemical weapon" are beginning to show!]
Lin Qingyue forcefully ignored the System's snarky comment and addressed Stonebeard. "We are not allied with the Goblins; we were merely passing through. If the Moonlight Moss is deeper inside, we are willing to trade items of equal value or help resolve some trouble as payment."
She spread her hands to show her goodwill.
The Stonebeard Earth Spirit fell silent for a moment, seemingly weighing its options.
It glanced at the terrified Cave Dwellers behind it, then back at Lin Qingyue and Lin Xiyue. Finally, its slow, gravelly voice spoke again.
"Perhaps... your arrival is not a coincidence."
"The Foundation Hall has indeed encountered some... troubles that we cannot resolve on our own."
Its rocky gaze grew profound.
"If you are willing to listen, and prove your strength and goodwill, the Moonlight Moss—and perhaps even more—can be negotiated."
"After all, intruders who can break through the Goblin blockade and leave such a... 'lasting impression' on Wallclaw..."
"You are the first."