One person: I, Daoist Master, am a cultivator of immortality!

After obtaining the records of Gu refining, Chu Feng and Sun Yao returned to the inn without making a sound. Neither Sun Yao nor Feng Huo intended to reveal this matter, even though they had killed bad people, they were still committing murder and robbery.

Back at the inn, the master and apprentice were as usual. Perhaps the only one who seemed a little off was Fengping, who looked as resentful as a wronged woman.

Back at the inn, Sun Yao began to study the "Record of Gu Refining." This notebook divided the recorded Gu worms into three levels: Legendary, Peerless, and Unparalleled. Perhaps it was because lower-level Gu worms weren't worth recording in this notebook, since the total number of Gu worms recorded in this bamboo slip was actually quite small.

The simplest of these is the Living Gu King Serpent, followed by the well-known Golden Silkworm Gu. However, the Golden Silkworm Gu, which can be called the king of Gu worms, is merely a legendary Gu worm recorded in this notebook.

After all, even the Gu-body Saint Child was merely a peerless Gu, and the so-called peerless Gu worm was simply something that was difficult to achieve. In fact, it was just a concept, and there was no successful case of its creation.

Is something that uses time as a guide and the waters of the river of time as its material something that ordinary people can achieve? At least for Sun Yao, it can only be a fantasy right now.

However, there were a few types of Gu worms in this notebook that he could refine, such as the Living Gu King Snake and the King Gu Golden Silkworm mentioned earlier. Of course, these weren't what he needed most at the moment. He had his eye on another type of Gu worm in the notebook, named the Silver-Winged Howling Arrow.

This is a type of Gu worm made from cicadas. The method of making it is extremely ingenious, making it ridiculously difficult to refine.

However, this did not diminish Sun Yao's interest in the Silver-Winged Whistling Arrow in the slightest, because the Silver-Winged Whistling Arrow's abilities were simply too good. First and foremost, the most important ability of the Silver-Winged Whistling Arrow was its ability to track enemies, which amplified a characteristic of cicadas: that is, the cicada senses the coming spring breeze before it even stirs.

The Silver-Winged Arrow can sense the fluctuations of any supernatural energy within a five-mile radius of its master; no enemy can escape its detection. A sphere centered on it will be detected by anyone who enters it. Most importantly, it can also be used as an attack weapon; its wings are incredibly sharp, and its body is indestructible, far surpassing the legendary Immortal-Slaying Flying Knife of Jia Family Village.

However, the difficulty of refining this thing is ridiculously high, the most important thing being how to ensure the cicada survives the refining process. Because during this process, the cicada, which is the main material, will suffer unimaginable treatment. First, the person refining the Gu worm needs to be able to recast its body with metal, and during this time, the cicada must be kept alive.

Although the flesh, recast from metal, becomes considerably heavier, its cicada wings, also recast from metal, combined with the power generated by its joints, are even more capable of propelling the body's movement, making it nearly 10 times faster than before. With the nourishment of Qi, it becomes even faster and more lethal. Its power is likely many times greater than that of an armor-piercing bullet; in this era, it can be considered a formidable weapon.

Most importantly, since the Silverwing Arrow's body is made of metal, finding a stronger metal will allow it to be upgraded and made even more powerful. Not only can nurturing it with Qi gradually increase its strength, but replacing it with an even stronger metal will also significantly enhance its power at once.

Although it was his first time refining Gu, he should have started with something simple, but Sun Yao immediately took a liking to the Silver-Winged Arrow. He didn't know why, perhaps it was just a matter of chemistry. Since Sun Yao's mastery of fire was already at its peak, keeping metal in a liquid state was a piece of cake for him; the most difficult part was ensuring the cicada's survival.

Sun Yao caught a full 120 cicadas on his first attempt, but not a single one survived the first stage. After all, cicadas aren't Wolverine; they can't just surviv on an adamantium skeleton. However, after 120 failures, Sun Yao finally grasped the key. The most important thing for a cicada to survive the first stage was to protect all its vital organs with his own energy. He even had to carefully protect its internal blood vessels and meridians, allowing the metal to replace its flesh and blood. Only in this way could he successfully refine the Silver-Winged Arrow.

However, this is easier said than done. The veins of a cicada are incredibly tiny; even its organs are smaller than a fingernail, let alone its veins. Yet, to successfully refine it, its internal structure must be perfectly preserved. The refining of the Silver-Winged Arrow actually tests the refiner's control over Qi. Only by controlling Qi with meticulous precision can the Silver-Winged Arrow be successfully refined without any mishaps.

Although he understood the principle, understanding and practice are two different things. Even though Sun Yao knew how to do it, he still failed more than 200 times. But there's a saying that goes, "Failure is the mother of success."

Sun Yao was willing to accept building a success from countless failures. Fortunately, the Lu family's birthday banquet was in the autumn, and they could still catch a lot of cicadas at the tail end of summer; otherwise, they probably wouldn't be able to refine the Silver-Winged Arrow until next year.

After more than 800 failures, Sun Yao finally crafted his own unique Silver-Winged Arrow. To be honest, despite the numerous failures, Sun Yao still smiled when he looked at his own Silver-Winged Arrow Gu.

The Silver-Winged Cicada Gu had cost Sun Yao a great deal of money. Although cicadas weren't valuable, finding so much metal at this time of year was very expensive. Therefore, Sun Yao resorted to double-crossing along the way. On their journey to the Lu family, Sun Yao robbed countless bandit camps. Of course, Chu Feng knew about this. However, since Sun Yao only robbed mountain bandits and horse thieves, Chu Feng was actually happy to see it happen.

Despite failing over 800 times and wasting countless sums of money, Sun Yao still ended up with a considerable surplus. Even though the three of them had originally planned to travel to the Lu family on foot, they were now all riding horses. This was all thanks to the shady dealings Sun Yao had engaged in along the way; now, he was quite a wealthy man.