The light brown medicinal soup, the pungent and unpleasant smell, and the suspicious medicinal residue that settled under the bottom of the medicinal soup, but Ivan didn't have any dislike and drank it in one go.

"Now that you're awake, come with me to the registration office and get your identification and some items. With that, Musian put the dishes that Ivan had drunk clean on the small table, then thumped his waist and said slowly.

"Good. Ivan nodded, just as he also wanted to see the environment of the underworld.

Pushing open the closed wooden door of the cave, what comes into view is a series of staggered vertical and horizontal, wide or narrow passages, each passage is placed on the left and right of a constantly burning oil and coal lamp, although the light is dim and not bright, but enough to illuminate the environment of the passage clearly.

Each passage leads to an unknown place, and at the end it is dark and unclear whether there is a way forward, and there is a wooden gate every ten meters in these passages, and behind each wooden gate there should be a simple cave, which is the residence of second-class criminals like Musien.

Ivan followed Musian, and the passage through which Musian took him was the widest, the widest, and the other narrower passages branched off from it.

This main passage is very clean, and it is very hard to walk on the road, and the mud on the walls of the passage is reddish, very dry and scattered, and there is no feeling of wetness.

"Old Mucien, there must be a lot of collapses here, why didn't you use load-bearing planks or some other safety measures?" Ivan picked out a little bit of crimson dirt from the wall with his fingers, and with a slight rub of his fingers, he could easily feel the small piece of dirt, like a handful of sand, easily dispersed.

"There are no load-bearing planks, not to mention that wood is a very scarce resource in the underground world, even if there is a lot of wood, where will they be willing to give us sinners who are about the same status as livestock in their eyes. Shaking his head, Musian's eyes were marked with a faint sadness.

"Is there very little wood in the underworld?" asked Ivan curiously, didn't he say that the resources of the surface world could be sent to the underworld?

"Although the resources of the surface world can be transported to the underground world, the process is very troublesome, and the transportation method is through a large magic array, but 9 due to the changing radiance of the magnetic field and force field of the underground world is very drastic.

So if it's edible ingredients, food, seeds, vegetables and other small items, it's easy, but if it's wood, large machinery is very difficult, and it is easy to fail in the teleportation process and then disappear into the endless spatial turbulence, which is why it is important to use our manpower instead of machinery in the mine until now. Musien explained.

"Since the disadvantages of a large magic teleportation array are so great, why not think of another way? For example, if you open a channel directly from the surface world to the underground world, it will definitely be a lot easier to transfer resources at that time. Ivan continued.

"Alas, the method you said was not thought of in terms of dungeon, not only did it come to mind, but it was also carried out in full detail, but in the end it failed, and it failed very quickly. Mucien sighed.

"What is the reason?" Ivan wondered.

"In the entire underground world, only the terracotta layer, the loess layer, and the black soil layer can provide oxygen for breathing, so the place where the human race lives is in these three layers. The terracotta layer is the nest of our second-class criminals and third-class slaves and the mining holes, 800 meters to thousands of meters from the surface, it is difficult to breathe, the soil is red, there are many particles, it is very dry, and it is also a layer of the three layers of soil that is prone to collapse.

The loess layer lives in the underground city civilian residential area where first-class citizens live, 300 to 700 meters away from the surface, it is difficult to breathe, the soil is brownish-yellow, there is humidity, there is stickiness between the soil, and collapse rarely occurs.

The Black Sun Society members and their families live in the black soil, about 200 meters above the surface, breathing is already very easy3, the soil is brownish-black, very wet, there are already a lot of subtle life and reptiles in the soil, coupled with very good safety measures, the collapse has hardly happened.

And the passage from the surface world to the underground world only needs to be opened to the black soil layer, of course it should be very simple, after all, it is only about two hundred meters, and it is true, the dungeon side easily opened a passage.

But within two days, the passage collapsed, and the reason was that the dungeon had always valued an ordinary life living in the black soil layer, a bug called an earthworm. This insect is known as the miracle bug of the soil scavenger, and it is very valuable, according to some pharmacists, earthworms are very valuable for medicinal purposes, which can invigorate blood circulation, prevent some heart diseases, or detoxify spider poison.

The reason why the earthworm is valued by the dungeon is that it can not only improve the soil and enhance fertility, but also it is an omnivorous animal, it does not eat except glass and rubber, and eats the rest such as humus, animal manure, soil bacteria, fungi, etc., as well as the decomposition products of these substances.

There is also a solution to the problem of how to deal with the daily garbage in the dungeon, and earthworms are particularly gluttonous and eat the amount of food equivalent to their own weight every day. About half of the food passes through the digestive tract and is excreted as feces. Therefore, the dungeon deliberately multiplies a large number of earthworms, scattered in the black soil layer, and the daily work of those earthworms is to dispose of the garbage generated by the dungeon.

But the dungeon didn't expect that the earthworm was an animal that was afraid of strong vibrations, and the passage from the surface world to the underground world transmitted mechanical vibrations was very strong, and after the earthworm was shaken, it would be restless and escape.

The scene of hundreds of thousands or millions of earthworms escaping is very terrifying, and even the black soil layer that has always been well secured has collapsed in a large area, and that passage is naturally not spared. Musien said slowly, there was an imperceptible tremor in his tone, the collapse of the year, thousands of people were crushed to death, and now in the faint collapse, it seems that the wailing of the souls of the dead can still be heard.

"Earthworm, I can't imagine that this kind of thing would produce such a big disaster. Ivan's heart was also a little shaken, and when his heart calmed down a little, Ivan thought of a new problem: "Old Mucien, no, didn't you say that the cave nest belongs to the terracotta layer, but why is the soil on the walls of your cave black-gray?"

"That, that's just that I don't like the color of the cave is too ugly, so I just went and bought a little black soil layer of dirt to decorate it. Mucien was stunned for a moment, and then replied calmly-

(To be continued.) )