Wang Guan and the others alighted from the vehicle, casually surveying Professor Liu's residence before accepting his invitation to step inside and proceed to the living room on the second floor.

Compared to Old Man Jin's home, Professor Liu's decor clearly possessed a more refined taste.

Snow-white walls adorned with several pieces of calligraphy and painting, coupled with elegant wooden furniture and an evergreen in the corner, lent the space an air of refined, antique tranquility.

"Welcome, everyone, to my humble abode."

Professor Liu smiled warmly. "Please, sit down freely. Don't be strangers."

After a round of welcoming gestures, he set about boiling water and preparing tea.

Only after several minutes of bustling about and pouring a cup of fine tea for each guest did he finally settle down.

However, Qin Yue had not forgotten the primary purpose of their visit. After taking a light sip of the tea, she went straight to the point: "Professor Liu, is the formula you mentioned for the Luan Glue real or not?"

"What, you still doubt it?"

Professor Liu chuckled lightly. "I can let you examine it, but..."

"But what?" Yu Feibai asked directly. "What are your conditions? Or how much money? Just name a price."

"Let's not talk about money; that's too vulgar."

Professor Liu waved his hand, chuckling. "It's not really a condition, more like a proposal."

"Stop beating around the bush," Yu Feibai pouted. "If you have a proposal, just say it. We can consider it."

That was right—consideration. On their way over, they had already agreed not to appear too eager, lest Professor Liu become overly confident and start making excessive demands.

"Just a small proposal," Professor Liu said, abruptly changing tack. "Oh, I didn't tell you before. I actually specialize in botany, and I'm intensely interested in plants—not just their roots, branches, stems, and leaves, but also their saps and resins..."

"The fox's tail is finally showing," Wang Guan and the others exchanged glances, their faces reflecting instant understanding. Their initial judgment had been correct; Professor Liu’s true target was indeed the item in the box.

"Since we are being frank," Professor Liu continued, establishing the true nature of the exchange, "there’s no need for subtlety."

Now that Professor Liu’s objective was clear, things became much simpler. Yu Feibai smiled, his demeanor softening. His tone shed its previous sharpness, becoming instead as warm and pleasant as a spring breeze. "Professor Liu, we understand what you mean. You want the contents of this box, right?"

Professor Liu smiled without answering, instead posing a question: "Actually, Luan Glue, boiled down to its essence, is just an animal-derived adhesive. Its bonding strength may not even surpass modern chemical glues. Why do you need it?"

They were all intelligent people, and they understood that Professor Liu's counter-question was not just idle curiosity; it was a subtle pushback. Just as Wang Guan and his group couldn't reveal why they needed the Luan Glue, Professor Liu would not disclose the true nature of the substance in the box. In essence, it was an issue of trust, leading to mutual probing.

"Very well," Wang Guan spoke up. "Now that the skylight is open, there’s no point in hiding anything further. We don't necessarily need to know what this thing is or its exact value."

"Exactly. Our objective is very clear: we want the Luan Glue, or the formula for the Luan Glue," Yu Feibai concurred. "If you possess the formula, give us the formula, and we will give you this item. A fair trade, how about it?"

"That can be done," Professor Liu replied, beaming. "That is actually the proposal I intended to make."

"Of course, this all hinges on the formula being useful—a genuine Luan Glue formula..." Wang Guan interjected, displaying caution. "Professor Liu, it's not that we don't trust you. But the item in the box is right here, tangible, visible, without any pretense of falsehood. A formula, however, is much harder to verify for authenticity."

"Precisely," Yu Feibai strongly agreed. "If you say it's real now, and we follow the formula only to fail to produce Luan Glue later, that would be a significant loss. It would be different if you had personally produced a tangible result using that formula before."

"I only have the formula; I have never refined the Luan Glue myself. Otherwise, I would have given you the finished product directly. However, since I dare to assert it is the Luan Glue formula, I must have confidence in it." Professor Liu said seriously. "And I must state beforehand: the formula is correct, but whether you can refine the Luan Glue according to it is your own business. I will not be held responsible."

"What do you mean?" Instantly, Wang Guan and the others frowned, their eyes filled with suspicion. That sounded suspiciously like an attempt to pull a fast one.

"Don't assume I am lying," Professor Liu shook his head gently and stated calmly. "Have you ever seen an ancient Taoist alchemist's formulation for elixirs?"

"A Taoist elixir formula?" Wang Guan suddenly began to grasp the situation. "Are you suggesting the Luan Glue formula is written in some sort of coded language?"

It was widely known that ancient Taoists, in an effort to mystify the masses and prevent leakage of secrets, wrote their cultivation "manuals" and formulas for divine elixirs in highly obscure language. They habitually used secret vernaculars to denote specific items, meanings indiscernible to anyone outside their own circle of peers or disciples. The most classic example was the talismans Taoists drew—a chaotic array of symbols whose meaning remained opaque to the common person, hence the term "ghost-writing." If the Luan Glue formula was written similarly, it wasn't impossible. After all, the Luan Glue itself had deep connections with immortal practitioners and alchemists, making the use of esoteric language seem entirely logical.

"This young friend is perceptive; you guessed correctly," Professor Liu said, delighted, giving a thumbs-up. "Ancient formulas are unlikely to be as detailed as modern proprietary recipes, specifying every step. All ancient prescriptions have a degree of broad generalization; mastery requires personal exploration. Luan Glue is the same. It only lists the ingredients, followed by a brief note that it needs to be steamed, boiled, and dried to achieve its final form."

"But these ingredients actually use abstract names like 'Kirin Horn' and 'Phoenix Beak.'" As he spoke, Professor Liu frankly admitted, "You will need to research and clarify what these names actually refer to. That is the situation. If you still wish to trade, I can fetch the formula immediately. If you refuse, I can't do anything, but I will ask one more thing: can you sell me the item in the box?"

Despite saying this, Professor Liu was certain Wang Guan and the others would agree to the exchange. During the probing, he had gauged their psychological bottom line—he knew precisely how much they valued the Luan Glue formula, which is why he decided to be truthful. Moreover, the truth was bound to surface eventually, and being candid now might leave a better impression.

"Qin Yue, what do you think?" Wang Guan turned to ask, knowing he was asking a superfluous question. Predictably, Qin Yue nodded without hesitation: "Trade!"

"In that case," Professor Liu smiled knowingly, immediately rising to walk out. "Please wait a moment."

"Bring out the original formula; don't try to fool us with a photocopy..." Yu Feibai called out loudly, still uneasy about Professor Liu’s integrity.

"I know," Professor Liu nodded and left. He returned shortly thereafter and placed an item on the table.

Wang Guan and the others quickly looked over. They saw a square box and a sheet of paper covered in writing. This paper, of course, was not a contract, but half of the formula. Professor Liu was not foolish enough to reveal the entire formula, lest Wang Guan's group memorize it and refuse the exchange. Therefore, he presented half the formula for their inspection; the complete text was engraved inside the box.

"This box is an artifact from the Han Dynasty," Professor Liu explained. "A few years ago, during the relocation of my ancestral home, I accidentally unearthed this item in a corner. I thought the box was quite exquisite, so I brought it back. While admiring it at home, I discovered writing engraved on the inner walls of the box. After research and investigation, I confirmed this is the Luan Glue formula."

"The item does look rather fine. Could this have been the vessel that originally contained the Luan Glue?" Yu Feibai speculated, a notion Wang Guan agreed with. Upon closer inspection, the box was cast from brass, rectangular but lacking sharp corners. The surface was decorated with motifs of auspicious cranes and clouds, perfectly fitting the ancient fascination with immortals. In a sense, using such an exquisite bronze box to contain the Luan Glue was not beneath the item's dignity.

Regardless, studying the formula was the priority. Everyone’s gaze settled on the paper, which bore a few lines of writing. Not only were there the unreliable materials like 'Kirin Horn' and 'Phoenix Beak,' but also other ingredients, including certain oily and resinous plant components.

"This is two-thirds of the ingredients," Professor Liu stated unequivocally. "Although a few crucial components and the refinement process are omitted, by observing the small details, you should understand that I am not lying."

"Qin Yue," Wang Guan murmured, hesitating slightly. "What do you think?"

"It seems genuine," Qin Yue nodded lightly, her bright eyes shimmering with a mixture of surprise and joy. Years of dedicated searching had finally yielded fruit; the excitement swelling within her was indescribable. Her restraint now only proved how composed and magnanimous she truly was.

"In that case," Wang Guan instantly declared, crossing his hands over the table and sliding the two boxes into his possession, "Professor Liu, we have a deal. Do we need to draw up a transfer agreement or anything formal?"

"Haha, it's a small matter; no need for such formalities," Professor Liu replied, a happy smile spreading across his face. "Though this is our first meeting, I know you people won't go back on your word or break a promise..."

"Naturally," Yu Feibai nodded proudly. But noticing the look of barely contained excitement in Professor Liu's eyes, he couldn't resist asking, "The item is yours now. Can you tell us what this thing actually is? Even if it’s a resin, which tree does it come from, and what exactly is its function? Surely that doesn't need to remain a secret anymore?"

"Well..." Professor Liu hesitated, considering for a moment before finally smiling. "It’s not that I don't want to tell you; it's that I fear you won't believe me if I do."

"How so?" Yu Feibai grew even more curious, his thirst for knowledge surging. He thumped his chest. "Don't let our youth fool you; we've traveled far and wide over the years and seen all sorts of strange and unusual things. Your explanation holds water, and you have physical evidence. We have no reason not to believe you..."