At that moment, Yu Feibai understood, a spark of excitement lighting up his face.

It is necessary to explain here that the so-called Xu Madam was not a woman, but a strapping, iron-willed giant of a man. Fú (), in this context, is not the character for husband, but is pronounced with the second tone, sounding like fú (, fortune). He was a famous master swordsmith from the State of Zhao during the Warring States period.

Historical records state that when the Crown Prince Dan of Yan sent Jing Ke to assassinate the King of Qin, he sought the sharpest daggers in the world and obtained the dagger forged by Master Xu of Zhao. He paid one hundred jin for it, then had an artisan treat it with poison, testing it on men; the moment the blade touched their skin, they instantly died.

This meant that the dagger forged by Master Xu was incredibly sharp. After Crown Prince Dan acquired it, he had it laced with poison, making its lethality even more profound—truly a weapon that killed upon contact, fatal with the slightest drawing of blood.

"So, this dagger is something that Jing Ke actually used?"

For a moment, Yu Feibai was utterly astonished: "Where was it found? Could it be in the Mausoleum of the First Qin Emperor?"

"...That is a secret." Elder Hou chuckled, offering a response that seemed evasive but was, in fact, a form of confirmation. Wang Guan and the others understood his meaning and, content with the silent acknowledgement, refrained from pressing further. Instead, they quickly picked up the dagger to examine it closely.

Just then, Elder Hou cautioned them: "Be careful. There is still residual poison on the blade. Though its potency has waned, if it wounds someone now, the resulting complications would be extremely troublesome to handle."

Hearing that the object was dangerous, the group adopted a more cautious demeanor. They gingerly drew the dagger from its sheath and immediately saw a weapon of rather peculiar design, imbued with an ancient, rustic aura.

After a moment of scrutiny, Wang Guan felt the dagger matched his imagination: it lacked the sharp, obvious gleam of new metal; the color of the edge was even somewhat dull and lusterless. This was entirely expected—after all, this was an assassin's weapon; its glint naturally needed to be restrained. If it shone brightly, it would clearly be a warning to the intended victim.

Of course, Wang Guan also noticed that beyond its archaic shape, the grain pattern on the blade appeared somewhat disordered—or perhaps like a tangle of messy thread, utterly chaotic and without any discernible regularity.

Furthermore, at the tip of the blade, the two spine edges protruded slightly, forming a silhouette that resembled a cross shape where they met the point. Although this cross-contour at the tip was not pronounced, it was a feature that gradually evolved in design.

With Wang Guan's knowledge of cold weapons, he immediately understood that the "tangled thread" pattern contained minute gaps, perfect for retaining poison. Moreover, once thrust in, the cross-like profile would maximize the opening of the wound, making it difficult for it to close. Under such circumstances, anyone stabbed by it was guaranteed a fatal result from a single thrust.

"What a dangerous thing."

Having deciphered the dagger's structural principles, Wang Guan couldn't help but sigh softly. It was no wonder that ancient literati often lamented that weapons were inauspicious objects, unfit for a gentleman, to be used only out of dire necessity.

Perhaps based on this sentiment, assassins, who were highly revered before the Qin and Han dynasties, gradually faced suppression; their standing worsened generation after generation, eventually becoming a despised profession by the Song Dynasty.

"It is indeed dangerous,"

At this moment, Yu Feibai wholeheartedly agreed: "Don't let its unassuming look fool you; if you were actually stabbed, with the medical knowledge of ancient times, it was absolutely a dead end. Speaking of which, Jing Ke was rather foolish. He was an assassin; why didn't he just use the knife to stab directly? Why all the unnecessary theatrics? It led to failure and even implicated his patron (Crown Prince Dan)."

After the assassination attempt, the First Qin Emperor was furious. The State of Yan, in an attempt to quell his wrath, offered up the head of Crown Prince Dan. Yet, even so, the State of Yan could not escape eventual conquest.

In a sense, Jing Ke, the killer, was indeed somewhat negligent; compared to his predecessors, like Yu The Lean and Zhuan Zhu, he fell short by more than just a little. Yet, strangely, Jing Ke remains the most famous.

The reason for this is that he benefited from the fame of the First Qin Emperor. Conversely, it wasn't that Jing Ke was exceptionally skilled, but rather that Qin Shi Huang's renown was so immense that anything connected to him was sufficient to be passed down through the ages and endlessly discussed.

"Elder Hou, the next room, what treasures does it hold?"

The human heart is never satisfied. After admiring these divine weapons, Yu Feibai eagerly inquired again, his eyes full of anticipation. He was confident that what they were about to see next would not disappoint his expectations.

"No rush, it’s just a few steps away; we'll know soon enough," Elder Hou kept his secret with a smile and then continued to lead the way.

Moments later, the group entered a vast space. Compared to the previous room, this area was furnished in a more advanced manner. Upon entering, Wang Guan immediately noticed that the flooring and the four walls were covered in special materials, and devices were installed in the ceiling.

In short, everything in the space gave off a high-tech feeling, much like a large-scale research laboratory. However, on second thought, this was a secret research base...

With that thought, Wang Guan smiled faintly and began to observe more closely. This space resembled an exhibition hall more than a laboratory, because objects were suspended along all four walls.

At first glance, these objects appeared to be paintings and calligraphy. However, these pieces were quite special; they were not simply hung on the wall but stored within transparent glass casings. Looking closer, Wang Guan also discerned some inexplicable substance within the glass enclosures.

Discovering this detail, Wang Guan could surmise that the glass casings without the visible substance might be vacuum-sealed environments. Such extensive high technology, employed just to protect a few pieces of calligraphy, indicated that these artworks were certainly extraordinary.

"What kind of paintings are these?"

Yu Feibai also grasped the significance and hurried over to look.

"It’s landscape painting..."

After gazing for a moment, Yu Feibai expressed a degree of approval: "They are quite nicely painted—grand and majestic, with beautiful scenery."

"Quite nice?"

At the same time, Elder Zhou chuckled: "This is the Three Hundred Li of the Jialing River Landscape, painted personally by Wu Daozi—a legendary, top-tier masterpiece. How is it that in your estimation, it only rates as 'quite nice'?"

"What?"

Upon hearing this, Yu Feibai froze. Wang Guan, standing nearby, was similarly stunned, his shock evident on his face.

Regarding Wu Daozi, there was no need for further introduction; the title 'Sage of Painting' alone explained everything. Furthermore, the Three Hundred Li of the Jialing River Landscape was no ordinary work, but a famous painting that left a deep mark on history.

Legend has it that during the Tianbao era, Emperor Xuanzong of Tang suddenly recalled the scenic beauty of the Jialing River in Shu, finding it picturesque and fascinating. He commanded Wu Daozi to travel by express post to the Jialing River to sketch en plein air. Upon reaching the river, Wu Daozi wandered along its banks, gazing into the distance. The excellent mountains and waters, every scene and vista, were deeply etched into his memory, and he didn't create a single preliminary sketch.

When Wu Daozi finished touring the mountains and rivers of the Jialing River and returned to Chang'an, Xuanzong asked him about the painting process. Wu Daozi immediately took up his brush and ink, beginning to sketch on the palace wall. In just one day, he rendered the three hundred li of the Jialing River's enchanting scenery onto the surface, with every mountain, every stream, every hill, and every valley proving captivating, drawing endless admiration from viewers.

"How is that possible?"

However, Yu Feibai was highly skeptical: "Wasn't the Three Hundred Li of the Jialing River Landscape painted on a palace wall? During the An Lushan Rebellion, the mural must have been destroyed. Even if it survived the fires of the An Lushan Rebellion, during the late Tang warlord uprisings or the wars of the Five Dynasties and Ten Kingdoms, the city of Chang'an must have been reduced to rubble. How could the mural possibly still exist?"

One had to admit that Yu Feibai made a sound point. That was the major drawback of frescoes: they were easily destroyed by any natural disaster or man-made catastrophe. Therefore, very few ancient murals have survived. Even those that have were usually preserved in places less likely to be reached by conflict, such as the Mogao Caves in Dunhuang or the Longmen Grottoes, and so on...

In any case, the imperial palace was certainly not among them, as palaces were always primary targets in military conflicts. When fighting broke out, various disasters like military action and fire were frequent, and a single mishap was enough to turn an artist's life's work into ash.

"Why is it impossible?"

At the same time, Elder Qian smiled faintly: "Didn't I tell you before about a technique called 'Stealing the Sky and Changing the Sun'?"

"Stealing the Sky and Changing the Sun!" In an instant, Wang Guan understood, and he immediately noticed that the image inside the transparent casing was indeed not a mural, but a thin layer of bó (, thin) cloth.

"Someone managed to create a tracing of it before the mural was destroyed."

As he spoke, Elder Hou showed a degree of relief mixed with resignation: "However, it is still just a copy, and after centuries of aging, it can only be barely preserved through soaking in special medicinal solutions. If it were displayed casually, or handled roughly a few more times, the painting would genuinely be ruined."

"What we need to do now is develop a more persistent solution to fix the painting in place, and only then can we consider other options. Perhaps in the near future, it can be displayed openly."

Elder Hou was very optimistic, which made Wang Guan and the others nod repeatedly, sincerely hoping that day would arrive soon. Sharing joy is better than keeping it to oneself; treasures like these truly deserve to be appreciated by more people.

After all, this place held not only Wu Daozi's Three Hundred Li of the Jialing River Landscape but also several murals by anonymous artists. The reason they were anonymous was that murals rarely carried signatures. However, judging by the style, they were likely masterpieces from that era, displaying ingenious composition and exquisite brushwork beyond the ordinary.

But Yu Feibai was still focused on the possibility of even better treasures within, so after appreciating these murals, he immediately urged Elder Hou to lead them onward to another space.

Upon entering this new area, Wang Guan keenly sensed something amiss with the light source and instinctively looked up, feeling a mixture of surprise and delight.

"What is it?"

Yu Feibai was not slow to react; noticing Wang Guan’s movement, he looked up as well. After one glance, he was stunned into silence. After a long moment, he recovered and exclaimed in shock: "What a massive luminous pearl!"

"Incorrect, it’s not a luminous pearl,"

However, Elder Hou countered, then smiled: "But it is certainly a famous jewel from history!"