Li Shisan originally thought that the tube was connected to something like an oxygen cylinder, but something was not quite right.

During the journey into the abyssal forbidden area for a few months, the number of oxygen cylinders had to be transported by truck, and the length of the tube was less than the chest, so it was impossible to breathe with the oxygen cylinder.

Later, I learned that this elephant trunk tube is a part of a filtering respirator, and only through the structure of such a long tube can it be filtered layer by layer to purify the air that is barely suitable for direct breathing.

If you use a spiritual weapon-level filtering technique, you can indeed compress the volume of the filter structure, making it thin and small, even close to an ordinary mask.

The side effect is that the spiritual weapon consumes the spiritual element of the cultivator, and every breath must be dissolved with its own spiritual element.

The seemingly clumsy elephant trunk filter respirator is only a spiritual material, and does not require additional spiritual elements to operate.

Li 13 took out something similar to a gas mask from the drawer.

Yuyuan University had winter vacation, and the money leopard handed over the self-developed filter respirator to Li Shisan before moving out of the dormitory.

The Golden Leopard version refers to the materials of the Yuyuan University Library, and the style is different from the official practitioner department, such as adding a trumpet-like structure to the mouth and nose of the gas mask.

The look is a reference to the Pea Shooter, or the Trumpet Sprout from the Pokémon World.

The treatment of the mouth and nose part of the two filter respirators is different, and the same feature is that it is large.

The elephant trunk tube or the trumpet-shaped pouting is due to the need for a large area to contain a material structure that is large enough to filter the layers of magic.

It looks like it's presentable, but I don't know which one is better.

The money leopard left a message saying that he could only go so far for the time being, and the laboratory could not simulate the environment of the abyss forbidden area, and there was no way to modify it further.

"Money Leopard is a good classmate."

Li 13 was very satisfied with the second-generation finished product that the Golden Leopard took.

The reason why he was able to get such a well-developed filtering respirator was only because Li Shisan took him into the shallow forbidden area, and the three cans of sampling specimens obtained at once met the standards of Yuyuan University.

Coupled with the hard work of the money leopard in his homework, three samples given by the analysis teacher met the standard, and the results were among the best.

This is the top student of Yuyuan University, and the gold content is explosive.

But Li Shisan always felt that he was still taking advantage of others, so he took him to get a few more cans of monster samples when he had time.

Then came the final exam...

To be reasonable, Li 13 didn't receive the exam notice until the winter vacation, it must have been Dean Qian and the teachers who explained that Li 13 was okay if he came to the exam, or if he didn't come to the exam.

After handing over those monster crystal nuclei, the sampling basic course of the freshman monster ecological research major has no value at all.

Got up and got dressed, took out his mobile phone to contact the dean's secretary, Li Shisan wanted to see the encrypted information allowed by Yuyuan University.

Yesterday, I had already communicated with Zhang Mad clearly, and I can go to the official cultivator department to read the information at any time, no problem.

Yuyuan University is not clear, in case the school's confidential archives are not open to the public during the winter vacation, and the principal and teachers are also on vacation, it will be called a tragedy.

"Li Thirteen?"

The dean's secretary had been explained in advance and knew that Yuyuan University had given Li 13 permissions.

"I want to go and see the materials today, okay?"

"Okay, no problem, I'll give you the temporary pass, and you can use the card to enter the confidential archives in the future."

"Thank you."

Dean Qian was going to go to other districts for inspection at the end of the year, and did not stay in District 6 for the New Year, but fortunately, the dean's secretary stayed to take care of the management affairs in the early stage of the winter vacation, and Li 13 successfully received a temporary pass.

The dean's secretary reminded that the temporary pass card is targeted, and you can only view the corresponding information that has been entered in the card, and the time limit is one semester.

The conversion time of one semester is half a year, and by then, Li 13 may have left the withered world, which is definitely enough.

The "Confidential Archives" of Yuyuan University is a special place that is not open to the public, and it will definitely not be able to locate it with a mobile phone map.

"It's actually on the ground floor of the teacher's cafeteria..."

Li Shisan originally thought that the confidential archives were mostly located near the office buildings of senior managers, or on the rooftops of important classic museums.

No matter how you think about it, you can't arrange the storage of confidential things in the basement of the cafeteria.

If you pickle pickles in the canteen or store pickles in the cellar, you are equivalent to being neighbors with the most valuable materials.

Pickles の highlight moments.

Behind the cafeteria, a small door adjacent to the food ingredient passage requires a card to enter.

Li 13 took out the temporary pass card and pressed it at the swiping place, a bit like the entrance of the elevator door.

For ten seconds, the door did not open, and after another minute or so, a staff member manually opened the door from the inside.

"Is it so primitive?"

The staff responded with a smile, "Li Shisan, right, the confidential archives room is one of the most important places in Yuyuan University, no kidding." ”

"Understand, understand."

Led by the staff, Li 13 entered the special sunken passage of the confidential archives, and under his feet was a staircase with a very obvious metal texture, which felt a bit like entering a subway station.

"Li 13, your temporary pass card can only access limited information."

"I know, I'm not interested in anything else."

Li 13 asked where the corresponding information was located and how to find it.

These problems are like entering the library of Yuyuan University for the first time, and I am not familiar with the structure of the tube, so I need to use the retrieval system.

Of course, the Confidential Archives does not provide retrieval services to holders of temporary cards with limited access, and the gameplay is different from that of a normal library.

The staff arranged Li Shisan into a nearly airtight space, except for the ventilation vents sealed by iron mesh in the two corners of the ceiling.

The room is about five square meters, with a small toilet in the room.

In the center of the main space is the boss's desk, which is a very wide and long style.

In addition to the matching chairs and spare chairs, and drinking water in the corner, all that was left was a simple pen and paper on the table and a small computer that could only be connected to the internal operating system.

"Student Li Shisan, you can read the materials in this reading room today."

"How do I get the information I want to see?"

"Swipe the card on the small computer, the screen will list all the information you have permission to obtain, check what you want to see, and the staff will help you into the room."

"Oh, thanks."

The communication equipment, spiritual objects, metal objects, paper and pens that you carry with you must be temporarily handed over to the Confidential Archives for safekeeping.

Li 13 sat down on the wide chair in the room, a bit like ordering food in a single private room.

Before closing the door, the staff reminds that the door will be locked after closing, and the reader cannot move around freely.

If you want to leave, you can contact the staff on the computer or the intercom on the door.

After reconfirming that there was no problem for the time being, the door was closed, and the sound of the thick latch locking could be heard.

"Natural bird, can you teleport here?"

Natural Bird: No, you can't teleport indoors unless you start a battle and use teleportation to get out of the combat range.

The Secret Archives is subject to a high-intensity barrier blockade, making it impossible for the Typhoon Signal to pass through the entity and then exchange venues.

"Dragon King Scorpion, can you dig a hole?"

No problem.

Dragonlord Scorpion says yes: the burrowing skill returns to the building/maze entrance by default when not in combat.

If you can dig a hole, it means that the piercing rope can also have the same effect.

Confirming that he could leave the current environment at any time, Li Shisan opened the small computer on the table with peace of mind...