Underground tunnels are generally divided into deep burial and shallow burial, generally speaking, if the tunnel is under the street, and the line of the tunnel is affected by the street, its direction is along the direction of the street, then it belongs to shallow burial. If the tunnel is buried relatively deep, and its line is not affected by the street or other buildings, and can freely pass through the ground, this form is deep burial.

There are many differences between shallow and deep burial, with shallow tunnels having a longer distance and deep tunnels being shorter. The construction method of shallow burial is the open cut method, while the deep burial is generally constructed by the shield method or the mining method.

Li Qing walked into the underground tunnel for a while, and found that the underground tunnel structure here is not exactly the same as the traditional tunnel configuration on the earth, and some places are even completely incompatible with the tunnel concept he understands, and it is completely supported by some strange things, but the complexity of the road conditions here is somewhat beyond Li Qing's imagination.

Oh my God, what the hell is this?

Have you ever seen an underground tunnel that runs east and west like an ant's nest? Have you ever seen an underground tunnel that can be drained and opened to traffic at the same time? Hey? What are these things that haven't been dug up in front of you? I'm rubbing, high ...... High voltage wires! Power plant?! This, this, this......

Li Qing walked in the underground tunnel for a long time, this direction was not confused, but his three views were almost ruined, some of the scientific and technological products that were completely beyond his common sense completely made him feel confused, Li Qing couldn't help but secretly wipe his sweat in his heart and said, this Piltover, although some fields of science and technology have completely surpassed the earth, but this idea has not completely entered the modern society. The person who can design such things is definitely a crazy guy with an IQ higher than that of Albert Einstein.

The amount of work in this underground tunnel is far greater than Li Qing's imagination, the entire underground tunnel is like a large underground world, there are almost no people here, the structure of the twists and turns of the upper and lower layers is easy to make people lose their direction, just now that Caitlin didn't even remind himself to bring a distress machine, what if he got the wrong direction and couldn't go back?! Li Qing thought dissatisfiedly.

Li Qing walked forward for a while, facing the seemingly endless turns and endless straights, even Li Qing, who usually crosses dangerous places, began to have a sense of urgency in his heart. But I don't know why, the more he encounters this dangerous situation, the more excited Li Qing is in his heart, and he enjoys the excitement of saving the day every time, which is one of the reasons why he once chose to become an explorer.

Placing a tick on the hexagonal screws of a large iron pipe above his head again, Li Qing threw away the stone, took off the pen pinned to his ear, and added another piece to the dense drawings that had already been drawn in his hand. Looking at the drawings in his hand that were gradually plump, Li Qing nodded slightly, at this speed, in less than half a day, he would be able to completely understand the underground tunnel here.

"Uh-huh...... Lalala......"

The turn in this place had come to an end, and Li Qing was about to continue to the next place, when he just turned the corner, a slender figure in the pipe in front of him suddenly appeared in front of Li Qing with a pleasant slight humming sound.

Li Qing saw that the figure seemed to be a young girl with a long ponytail, a small leather coat, and a decoration that looked like a baseball bat on her back, and at this time her arm seemed to have just been lowered from a wall, because the light in this underground tunnel was not very good, so Li Qing did not see her face clearly.

"Oops! Hee-hee-hee-hee...... You're a little late to the truth!! ”

The girl seemed to have just finished the things in her hand, and saw Li Qing, who seemed to be patrolling here, the figure was stunned for a moment, and then suddenly laughed, only to see a thunderbolt suddenly appear in her hand, with a bang, smoke shot out, and with a slight footstep in the distance, the slender figure suddenly disappeared with the fading smoke, leaving Li Qing who stood in place with a confused face but didn't know what was happening.

“……？ what？ ”

After a period of silence, Li Qing had a big question mark on his head, walked towards the place where the girl was just now, and looked around again. Finding that the latter had indeed gone far away at this time, Li Qing couldn't help but give up looking for the latter to ask for a clear idea.

Alas, brother is just passing by, okay? Do you know brother? Girls now, alas.

"Click......

Li Qing sighed, and was just about to walk forward, when suddenly, a small sound of a clock appeared in Li Qing's ears.

"Huh? What was that? Li Qing's ears moved, the sound was not too obvious in the dimly lit underground tunnel, Li Qing calmed down, listened carefully for a while, and then, in an inconspicuous corner, a faint burst of red light shone into Li Qing's eyes.

"Huh? It's ......"

Li Qing turned on the flashlight above his head to take a look, but when he saw the object above his head that was flashing against the wall, his face suddenly changed drastically.

"! This...... This, what that little Nizi had been fiddling with on the wall just now was a timed thunderbolt?!!! "Look at this bowl-sized thunderbolt. Li Qing suddenly stood on the spot and jumped on tiptoe and shouted.

Li Qing panicked in his heart, and hurriedly looked at the time displayed on the latter.

…… Well, it's an alarm clock, which means that he can't know the time set by the girl just now!

Looking at the big shark symbol above, Li Qing's heart suddenly became calm, and he hurriedly walked along the road just now to see if there was such a thunderbolt in other places, after all, although the materials generally constructed of this underground tunnel are very strong, but if it withstands more bombardment from below, it may also lead to a collapse!

"Does that little girl know what she's doing?!"

Li Qing complained in his heart as he carefully and quickly looked around for a possible thunderbolt.

However, even though Li Qing found this path all the way, the timed thunderbolt he found was just the one he had just seen, so Li Qing returned to the storage place of the thunderbolt just now with a nervous mentality, and the thunderbolt was a thing that he often used in the exploration of those ancient ruins on the earth in the past, so Li Qing was not too unfamiliar with this kind of item like ordinary people.

After carefully weighing the power that the latter might produce, Li Qing decided to dismantle this thing first, after all, if this thing didn't get right, wouldn't it be ridiculous if it exploded and buried him here? He had a certain amount of research on the timed thunderbolt, so Li Qing took out a small pair of scissors from his spatial ring and carefully studied the thunderbolt.

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