Qi Tianyu deserved to be a good alchemist, and along the way, he not only told Feng Yu and Qingtian a lot of knowledge about medicinal materials, but also told them a lot of knowledge about all aspects of medicine refining, so that they had a lot of insight. Refining medicine is literally a fusion of medicinal materials, but it is actually very complicated. Broadly speaking, alchemy can be divided into one link: chemical medicine, condensation essence, melting pill, and spiritual endowment. The single link of Rong Dan requires many times of experience and subtle soul control.

The main need for chemical medicine is a general and accurate understanding of the elixir; Coagulation is to remove impurities from medicinal materials; Rong Dan is the fusion of medicinal materials into Dan; Spiritual endowment is the most important and risky link, requiring the alchemist to remove the weak spiritual wisdom that may be caused by long-term absorption of spiritual energy. In the prescriptions of high-grade elixirs, high-grade materials are generally with consciousness and weak spiritual intelligence, and the materials on some spirit beasts may even produce murderous spirits.

The level of an alchemist is divided into ten levels. Below level 3 are low-level alchemists, levels 4 to 6 are intermediate alchemists, levels 7 to 9 are high-level alchemists, and level 10 is a top-level grandmaster-level alchemist. In order to become an alchemist, one must have three major conditions: strong soul power, an innate sense of medicinal materials, spiritual power with fire attributes, or the ability to skillfully control flames.

Among them, the most difficult to meet is the second condition, the other two can be artificially controlled. The induction of medicinal herbs is really illusory, and it can't be artificially made up, so it can only be seen by talent. And testing this ability is also very simple, the herb will emit all kinds of light in the hands of those who have these properties, and in the hands of those who do not have such properties, there will be no reaction at all.

The three of them walked into the valley deep in the mountains, and the smell of medicinal herbs wafting in front of them shook their bodies, and their minds seemed to become clearer. Looking left and right, all kinds of strange-shaped flowers and spiritual trees are dazzling. Countless different medicinal herbs made Qi Tianyu smile widely.

The trio rests in a circular cave. This is the secret cave that Fengyu discovered after careful searching, which can lead to the belly of the mountain, and there are many twists and turns in it. Don't look at the small entrance of the cave outside, the space inside is very large, and when you enter the cave, the surroundings become wider.

The cave is empty, there are more than a dozen stone stalactites of all sizes, and there is a small stream along the stone wall. The inside of the cave is closed but not dark, because the stone walls are made of rocks containing luminous stones. Under the illumination of the luminous stone, the cave is glowing with a misty milky white light, which illuminates the stone stalactites more and more crystal clear. Everywhere is milky white, which looks dreamy and magical.

I found a place to sit, and in the middle of the valley was a bulging dirt bag, on which a few weeds grew sparsely. Feng Yu looked unpleasant, and kicked hard to break down the soil bag. The dirt was raised, and Feng Yu's right foot touched a hard place. What is it? Squatting down to peel off the dirt, I saw a corner of a black stone tablet exposed.

Could it be that there is something down there? Fengyu continued to dig, and after digging out all the soil layers above, he saw a square stone tablet buckled on the ground, about one zhang long, and the surface was pitted, full of traces of corrosion. Grabbing the stele with both hands, it lifted it hard, revealing a cavern below. After hesitating for a long time, Feng Yu was still ready to go down to see what the situation was.

The cave is not deep, and it is about a few feet down to the bottom. There was a wooden door on the side of the bottom, and when I pushed it, the door was completely rotten. When they went in, the three of them were taken aback. There are all white skeletons lined up inside, and there are tens of thousands of white skeletons as far as the eye can see.

All the skeletons are almost incomplete, some are missing arm bones, some are missing leg bones and skulls, and some even have only ribs left in the rib cage of the chest. However, although incomplete, the skeletons are neatly arranged in rows, as if someone did it on purpose. Feng Yu approached a skeleton, and when he saw an extra bone on the ribs on the back of the skeleton, he couldn't help but shrink his pupils, Wing Man! The extra wing bones are obviously winged people, and if you look closely, there are very few other races in these skeletons, and most of them are actually wing people.

What's going on? How could there be so many skeletons of winged people? Is it a cemetery? No, it is impossible for the cemetery to place the skeletons like this, why are there such large groups of skeletons in the Herb Valley?

In the vast pile of bones, the three of them used their hands together to advance into the depths of the cave. Some skeletons turned into ashes at the slightest touch, while others broke off and fell to the ground, and none of the skeletons could remain in their original state. The path they walked was littered with piles of white bone meal, mixed in the dust, making it look like a large co-burial tomb.

"What is this place?" Seeing this kind of scene, Qingtian couldn't help but look at Qi Tianyu, who was also full of shock.

"I don't know, I've never been here, I've never heard of it." Qi Tianyu's eyes were also full of surprise and uncertainty.

"These skeletons seem to be a long time ago, at least hundreds of years old." Feng Yu tore off a piece of cloth to cover his nose, ignoring the bone meal on his body, and slowly pushed forward. After walking for about half an hour, we finally came to the end.

Crossing a deep ditch in front of him, a small flat square came into view. In the middle of the square, there are several huge white stone pillars that are more than ten meters high, and there are nine in total. The stone pillars form a circle around the center of the square, and each one has several chains connected together, and between the chains is covered by a layer of turquoise light array, which looks like an enchantment.

Looking closely, there is a round stone table about a zhang in diameter in the middle of the pillar, on which are placed three rectangular boxes. From left to right, it becomes smaller, and the leftmost one appears to be a foot long and three inches wide; The middle one was reduced by half; The left and right ones are only the size of palms.

There was a slight grinding sound behind him, Feng Yu raised his head, and inadvertently, a tuft of hair close to the light array touched the turquoise light film. With a "snort", the hair turned into a flame within the range of green light, and it was burned clean in an instant. Feng Yu turned his head and saw the moment his hair was burned, so he quickly took a big step back.

What the hell is this, and it still burns things that come close? Feng Yu picked up a small stone and threw it at the light film, and the moment the stone touched the light array, a flame erupted, and it disappeared as if evaporating. This scared Fengyu. This layer of light film is too exaggerated, even the stone can be burned, and there is absolutely no return when you touch it.

After a meal, Feng Yu stared at the light array in a daze, there was still nothing he could do, and the other two also looked confused. There must be something good in these three small boxes that suddenly appeared, otherwise the defense would not be so tight, and the three of them walked around the light array a few times, trying to find a breakthrough, but this light array looked very tight, without a single gap, so that he couldn't start.

Inadvertently, Fengyu noticed a small protrusion in front of the three boxes, why did a small protrusion appear on the flat table? There was something weird, Feng Yu narrowed his eyes and looked at the small protrusion more carefully. The bottom of the protrusion has a ring of lines that are not easy to spot, and it looks like it should be pressable. Could it be that this is the control switch of this layer of light film?

But how do you open it when you put it inside? The person who designed this mechanism is really disgusting, obviously he doesn't want people to take away the treasure, he can only look at it but can't take it, isn't this a rush to death? Let's see if brute force can break it. Feng Yu found a huge stone in the cave and smashed it at the light film. There was a violent fluctuation on the surface of the light film, scattering layers of circles.

The boulder seemed to hit the water, leaving only a circle of ripples but not a single wave. With a thud, only half of the stone fell to the ground. Looking at the section where the stone had been melted, it was smooth, as if it had been cut by someone with a knife, and there were no traces of burning. Brute force can't work, so I can only try to see spiritual power.

Feng Yu condensed the immortal spirit power into a ball of light and slowly pressed it against the light film. This time there was finally a reaction, and the small balls formed by the light film and the water spiritual power condensed dissolved each other, and the color began to fade. A smile appeared at the corner of Feng Yu's mouth, and he was about to increase the output of spiritual power, when a green light burst out on the light film, and the faded light film suddenly returned to its original turquoise.

What's going on? Isn't it starting to fade? Feng Yu was stunned for a moment, then gave up after trying a few more times. No matter how much he increased the output of his spiritual power, the light film would burst into a cloud of green light after a few seconds of fading color, and then return to its original form. In this way, even if the immortal spirit power of the whole body is consumed, it will not be able to break through this light film.

The three of them were tired and sweaty, and they were still very puzzled by this layer of light array, and they couldn't open it despite their best efforts, so they could only stare at the three boxes with dry eyes. The immortal spiritual power was finally exhausted, and Fengyu had to stop the export of spiritual power. At the moment when her fingers left the light film, that golden true qi spontaneously filled the gap in the immortal spirit power and touched the light film.

Wait a minute! Feng Yu, who was just about to turn around and leave, couldn't help but pause when he saw a small hole in the light array, and when he walked over to take a look, a small hole the thickness of his thumb melted out where the light array and the golden true qi came into contact. The three of them were suddenly happy in their hearts, and they put their fingers next to the small hole, and the golden true qi that continued to pour out from their hands slowly expanded the small hole, and after a while, the original small hole expanded to several times the original size.

I didn't expect that the golden true qi would be useful for this kind of light film, why didn't I think of it? As that layer of light disappeared, the three boxes appeared naked in front of Feng Yu. She picked up the biggest one and looked at it a few times. The black box doesn't know what the material is, there is not a single gap, just a thin hole in the side, which looks like it needs something to insert in to open.

The trio continued their search, hoping to find some clues that would open them.