"Chief Divine! True sand for selecting iron, blowing furnace for iron smelting... Thousand Forging Technique?..."

A moment of "Paper-forged Sword", and the outcome is evident. The Kingdom's blacksmith, Matsushita Tetsusuke, changed his expression, his aura considerably diminished. Yet, in front of the old craftsman Tietian Zongyi, he still refused to concede, glaring at the other's severed arm as he insisted loudly.

"You keep talking about your Layered Thousand Forging, annealing and quenching, Mountain City Secret Technique... can you really forge, or can you only talk the talk?... How about we build an earthen furnace by the river and each forge a dagger to compare our skills?!"

"Ha! You youngster, still so stubborn!..."

Upon hearing about starting the furnace for blacksmithing, Tietian Zongyi's heart skipped a beat. With his old arm, how could he truly forge a sword? Yet his face remained confident, not giving Matsushita Tetsusuke a glance.

After a brief thought, Tietian Zongyi turned around, bowed, and saluted patiently listening Zuwaro. Then he took out a yellowed atlas from his bosom.

"Honorable Golden Chief! The Mountain City Secret Technique is not easily shown... but since it's for Buddha's charity, and far from the Mountain City School, all the past is like smoke dissipating... This old man shall impart everything to the apprentice arranged by the chieftain!... Here is a Forging Knife Atlas, which I drew myself in my early years, and I wish to present it to the Great Chief! Please look at this picture and listen carefully as I explain the forging technique of a fine Tamahagane knife!..."

"Oh? Forging Knife Atlas?"

Zuwaro took the atlas with interest and flipped through it. The first half depicted mineral selection and iron smelting, particularly illustrating many iron smelting tools. The bellows of the so-called 'Tatara Furnace' was as big as the furnace itself, with a little man forcefully pedaling it. Beside it, there was some Japanese script used by Japanese commoners, whose meaning was unclear.

"Chieftain, this part explains that the fire borrows the momentum of the wind, and the furnace temperature is related to wind speed! Therefore, the faster and more wind, the higher the furnace temperature can be. The higher the furnace temperature, the better the iron smelting. To maximize furnace temperature, one must set up giant bellows on both sides, using human foot power to continuously blow air into the furnace!..."

"Oh! Converting human power into wind power, blowing air into the furnace to increase temperature? I remember the Divine Revelation Scripture mentioned that there's a Divine Grain in the wind that aids combustion, so the more that enters the furnace, the more intense the combustion... That's possibly the explanation!"

Zuwaro pondered slightly, eyes brightening. He then pressed to the next part, seeing three images of the 'Thousand Forging Technique.' The first showed a little man forging a knife blade, the second showed a little man applying something to the blade, and the third showed a little man putting the blade into water.

"Chieftain, the first step of the Thousand Forging Technique is 'stacked forging'! First, take a piece of Tamahagane and forge it into a thin sheet with a hammer, then fold this sheet and continue forging. Although it's nominally called 'Thousand Forging,' generally, folding it 16-20 times to form an exquisite 'Thousand Forging Pattern' results in a fine sword with Yemono quality!..."

"However, this 'stacked forging' sounds simple; truly executing it tests one's skill, care, and endurance the most! Tamahagane must be forged evenly, with no irregular patterns, no bubbles or cracks! The forged pattern must be 'uniform and delicate', as orderly as possible. As the secret transmission describes it, it should be as beautiful as 'clouds'! A good-looking sword isn't necessarily powerful. But a powerful sword must be good-looking!..."

"Hmm... Beauty like clouds?... Powerful... Good-looking?"

Zuwaro, in contemplation, thought for a while before pointing to the second image and asking.

"Chief Divine witnesses! What's being done in this second image? Why is there something being applied to the blade?..."

"Oh! This second step is preparation before quenching... Applying different thicknesses of clay to the blade edge and spine..."

At this point, Tietian Zongyi paused, glanced at Matsushita Tetsusuke subtly eavesdropping, hesitating whether to reveal the 'true secret.' But considering the situation, he sighed softly, apologized to his long-deceased master, and forced a smile as he said.

"Chieftain, after completing 'Layered Forging,' before 'quenching,' there are generally two procedures that showcase the craftsman's skill! The first procedure isn't depicted in the drawing but is annotated as 'annealing'. The so-called 'annealing' is 'nurturing the blade with fire'! Heat the furnace to a 'cherry red', 'nurture the blade' in the fire for three to four hours, then bury it in ash to cool slowly. Once completed, the sword is 'comfortable,' its body softened, and ready for quenching..."

"And the second procedure before quenching is 'applying clay', depicted in this image... applying different thicknesses of clay onto the blade edge and spine, making the blade sharp and the spine tough after quenching!..."

"Hmm? What's the rationale behind this? The same steel, the same clay, why does just a difference in thickness result in sharpness on one end and toughness on the other?... Tetsusuke, why are you standing so close? Haha! So you don't know either?"

"Buddha! This is a Mountain City secret... Ah! In simple terms, it's not that mysterious. It's just about 'cooling speed'!..."

Tietian Zongyi looked around, sighed again, and gently revealed this crucial point. The eavesdropping Matsushita Tetsusuke was instantly enlightened, seeing a higher realm of skill!

"The faster the steel cools, the harder and more brittle it becomes, suitable for the blade. Conversely, if it cools slower, it becomes duller and more flexible, suitable for the spine... To control its cooling, the most practical method is to apply clay, apply sticky clay! If the clay is applied thicker, naturally quenching will cool slower, enhancing toughness. If the clay is applied thinner, cooling is faster during quenching, making it sharper..."

"And this third illustration, depicts the final step of quenching! Sometimes quenching uses water, and sometimes oil... The difference between water and oil lies in the cooling speed! There's a mnemonic verse: 'Water fast, oil slow'. Another line follows, 'Urine quenching makes it brighter'. It means that after adding urine, the quenched blade will have fewer cracks on the surface, making it smoother and more beautiful, and slightly improving the quality!..."

"Ah! So that's it!... Layered forging, annealing, quenching, indeed each has its rationale!"

Having listened to this detailed knife forging process, Zuwaro nodded in sudden realization! Although he had no experience in forging knives, the master craftsman explained it once, revealing the principles within, giving him an illusion that he already understood.

This Tietian Zongyi seemed to be genuinely skilled, not only 'knowing what it is', but also 'knowing why it is', and 'knowing all its whys'! It means he had already reached the level where he could integrate practice with theory. No, he also possessed the 'Secret Technique' from an ancient school's tradition...

Thinking of this, Zuwaro glanced at Tietian Zongyi and then at the atlas in his hand. He then pointed to the resting Tiger Vanguard, Hu Nu beside him, and asked one final question.

"Master Tie! Besides forging knives, can you forge other weapons? This long knife, Hu Nu says it doesn't feel quite handy, what weapon do you think would be more suitable?..."

Tietian Zongyi scrutinized, and Hu Nu grinned, which startled him so much two shivers ran through his heart. He dared not look directly at this 'Shantian Warrior' as strong as bear and tiger, and quickly glanced at the other's long knife and bone club. After a moment of contemplation, he replied.

"Chieftain, I've never seen such a majestic tiger warrior... If it's for foot combat, the most suitable weapon for him should be a Two-Handed Heavy Axe, at chest height, best to utilize his height and strength advantage! If for mounted combat, he could use a Thick Back Horse Saber, the blade should be widened and thickened. It doesn't need to be so long, about four feet would suffice..."

"And if suitable for both infantry and cavalry, actually the Tang people's 'Wolf Fang Club' or the 'Ghost Gold Stick' could be used. Heavy and sharp, capable of slashing, cleaving, pounding, and stabbing! But such heavy weapons can only be wielded effortlessly by true Tiger Warriors!"

"As for forging these weapons... the reason forging knives is the benchmark for master craftsmen is because it is the most difficult! A master craftsman who can forge a good knife can naturally craft axes, spearheads... with ease!"

"Good! Very good! Blessed by the Chief Divine! ...Master Tie, you are indeed a grand master among blacksmiths! Your Majesty will surely value you, providing you a real status and responsibility, perhaps even at Divine Power University... Haha! Just wait for the next batch of ships to arrive..."

After this trial was completed, Tietian Zongyi straightened his old back, Matsushita Tetsusuke lowered his head without speaking, Hu Nu blinked, and Zuwaro laughed heartily, speaking words in Nava not understood by the Japanese. After a moment of laughter, he forcefully patted Hu Nu's shoulder, pointed at the smiling Mori no Kiyoshi, and generously said.

"Hu Nu, give him the Gold Talisman!"

"Great Chief, how many pieces?..."

"Twenty pieces!..."

"Ah?!"

Upon hearing this, Mori no Kiyoshi's smile froze, incredulously rubbing his ears. After hesitating for several moments, he still respectfully smiled and said.

"Ahem! Great Chief, you remembered wrongly... The previous agreed price... well... it was ten pieces, ten kilograms of gold..."

"Chief Divine witness! I know!"

Zuwaro nodded, gently patting Tietian Zongyi's single arm. Then, with a light and airy sentence, the one-armed Tietian Zongyi's eyes turned red, and he silently pressed his lips together.

"But I say twenty pieces, it means twenty pieces! Twenty kilograms of gold! He is a real grandmaster, and he's worth this price!..."

"Hu Nu, give him the Gold Talisman!..."