The threat of mutated creatures and zombies is truly nerve-wracking to humans, their minions can tear the earth apart, their alienated skin can withstand bullets, and their muscles are as strong as machines that don't get tired. If you want to resist such a terrifying monster, even the barrier made of steel will one day be destroyed under the erosion of the black rain and the violent attacks of the monsters. Without the protection of defenses, mutated creatures with incomparably flesh and blood will rush into it in droves, preying on delicious humans.

According to the mental power scan that covers the entire planet, the human settlements on the planet's land and sea, with different scales and protective priorities, are constantly being tested by mutated creatures. Wherever there is a problem in the construction process, the mutated creatures will immediately make the humans living in the congregation understand the consequences of negligence. And the human gathering place that Xun Xin and the others are about to enter is also one of the largest among all human gathering places.

As the convoy approached its destination, it was impossible for humans, who had been strengthened in all aspects of the planet's power, to see the gray-black wall at the end, appear in front of everyone. Under the detection of spiritual power, the structure of the city wall and the composition of the materials were transmitted back to Xunxin's mind.

"It's really a sturdy parapet, and if the entire convoy runs out of energy to attack it, I'm afraid it can only scratch the paint on the wall, right?"

"Of course." When it comes to the wall, the members of the team are full of confidence. "It's the defensive wall that separates millions of people from mutated creatures and zombies, and it's the proudest building in the entire gathering place."

Although I think that the color palette is no different from the architectural style and the style that the demon likes, the designer's aesthetic must need to be treated in the hospital. ’

The outermost layer of the entire wall is a five-meter-thick protective layer made of an alloy that is familiar to the heart-seeker and is used to protect the outer armor of the vehicle. In a casual conversation with Wang Qiang, Xun Xin learned that the armor that makes up the exterior of the car hull can only be smelted with facilities of the highest scientific and technological level, and the armor needs to be mixed to improve the strength of trace metals can be said to be in short supply under the current shortage of minerals. Every convoy operating in the wilderness is desperate for life-saving armor. In the major human settlements, whenever there is such armor that can be traded in a barter manner, the entire trading place will be crowded with people who swarm to it. Such rare armor was used as part of the structure of the city wall, and there was not the slightest trace of water, and it was actually made of extremely strong alloys.

"This wall is a little stronger than most of the smaller ships I have without a protective barrier......

After roughly estimating the strength of the armor, this armor layer alone is afraid that a few close shots from the main gun of a 460mm battleship can at most scrape off a layer of paint, not to mention ordinary mutated creatures, even if they grind their claws and break their teeth, they can't penetrate the barrier created by the blood and sweat of this painstaking gathering place - in the true sense of the word, beyond the protection of the word "iron wall".

The protection of the steel walls on the ground alone is not enough to protect against the threat of mutated creatures, you must know that there are tens of thousands of flying creatures in nature, and after various mutations, Xun Xin said that he also saw a flying shark gliding in the air as it spewed a high-pressure column of water that could cut through the steel. In order to fight against the flying monsters whose walls could not resist them, the inhabitants of the gathering place even covered the sky of the entire human gathering place with carbon nitride glass stronger than diamonds, and made a three-stage sandwich protection to prevent the failure caused by the breakage of the single-layer roof for some reason. In order to compensate for the fragile nature of carbon nitride, a large number of alloys made of the same material as the city walls were made into brackets to control the high-hardness glass switches. When it rains with extremely corrosive black rain, high-strength carbon nitride glass canopy is one of the few building materials that is not affected by the black rain. With such a high level of protection, it would take a lot of effort for even the most feared monster to break through the defense.

With a sturdy shield, it's not enough to withstand the tide of mutated creatures. As the saying goes, no matter how strong the defense is, there will always be a day when it will be broken, and no matter how strong the defense on the perimeter of the gathering place is, it is difficult to guarantee that no monster will be able to break through the city wall. Moreover, monster attacks will always leave traces on the protective measures, and repairing armor and replacing the crystal plates on the glass canopy is also a waste of money and material resources. In that case, wouldn't it be possible to use weapons to break the attacking monsters to pieces to avoid damage to the protective equipment as much as possible?

Equipped at the top and center of the city wall is a particle rapid-fire cannon that is enough to make ordinary people suffer from dense phobia, presumably when the monsters invade, the first generation of continuous-fire weapons made by humans on the verge of life and death will give monsters a good taste of what is called a high-tech barrage. For large monsters that are huge and have a strong regeneration ability, or whose carapace is so strong and heat-resistant that even high-energy particle beams can only burn a few scorch marks, they are awaited with heavy weapons mounted on the top of the city walls. The large-caliber particle heavy cannon that can stuff three or four people into it, and the projectile projectile projectile projectile that is ejected in just one minute is equivalent to a dense array of electromagnetic cannons with the power of dozens of tons, and the heavily armed soldiers on the city wall who are loyal and fully armed constitute this shelter that will not fall in the apocalypse.

"The indigenous people of this planet...... The ability to innovate in a desperate situation is beyond my imagination......" The group stopped their vehicles at the entrance to the human gathering place, and were scrutinized by the guards. It seems that in order to establish the prestige of the convoy that came here, the soldiers who inspected the convoy turned out to be all modified people, equipped with individual protective stance generators, multi-functional particle hand cannons, and **-style melee high-frequency cutters with suitable weapon confrontation configurations regardless of distance and proximity, and even the equipment used by the former leader of this convoy was only slightly better than them.

"Uh...... Yes, under such difficult conditions, it is possible to build such a large-scale, war city? "For Kirito, who had just become an official Infinite Apostle and was pulled into an urgent mission to fight to the death, it was beyond his imagination that this fortress city that could accommodate at least 100,000 people could be built by humans in the face of almost extinction. And the backbone of the team, the most experienced heart seeker 'sees' is not only the surface of the city, as the most important support of human beings in danger to resist mutated creatures, how can it be just extraordinary in size. Perhaps even the vast majority of the inhabitants of this steel city do not know, but with the spiritual power of the heart, there is not even the slightest possibility that the secrets hidden under the earth of the human gathering place are hidden.

"Xunxin, you said that under the ground of this city, there is actually a drive equipment that can move the city at a critical moment?!" Upon learning of the discovery, almost all members of the team thought that the heart was joking. Indeed, the idea of moving an entire city is so far beyond the imagination of the Aborigines that even the Infinite Apostles, accustomed to seeing the majestic creations of rare and majestic creations, could hardly believe that the aborigines could have reached the point of moving the entire city with the help of incomplete technology.

"You should know that the tower in the center of the city is the console used to control the city's defense equipment, right?" After receiving everyone's affirmation, Xunxin took a sip of water and continued: "However, the human gathering place where we are staying does not mention any underground defense measures. I've seen all the information you have, but all of the references to this place have been lightly mentioned when they are mentioned in relation to the underground part. I'm afraid it's the trump card that wants to hide underground and escape from here at the most critical moment......"

As the psychic scan deepened, the situation of the entire underground facility was remembered by the heart. Although the scale and complexity of underground facilities are among the largest and most sophisticated in the entire human settlement, if not on the entire planet, it is precisely because they are so large relative to the population base that the likelihood of them working properly is close to zero if they are well maintained.

Even so, these people are too whimsical...... A giant city with a total weight of nearly 100 million tons, if you want to move it, you may be far from relying only on the nuclear reactor complex in the underground part...... After a simple inspection of the underground equipment, Xun Xin had to say a few words: "The function of these underground equipment? It may be possible to solve the work problems of some people, but it takes a lot of labor to maintain such a well-developed and useless equipment. ”

Moving the city or something, if it's not extremely abundant in energy and the speed of energy output is greater than the consumption, then it's better to play while playing, the civilization level of this planet can't play the city that can move on the ground. In addition, the nuclear reactor used to move the entire city is also a big problem in terms of safety, once there is a leak and instability, and the staff on duty fails to deal with it in time, the whole city will be lucky to become a dead city under the high-intensity nuclear radiation, and if you are unlucky, it will fly directly into the sky, and become the largest fireworks in the history of the planet may be a very commemorative event.

Closing the book in the mental space called "Teach You to Analyze Aboriginal Black Technology in Three Minutes", Xun Xin said that according to this book, the people who designed the nuclear-powered mobile city definitely had the idea of blowing up the sky with mutant creatures at the last moment. As the inspection progressed, it was the turn of Xunxin and the others to conduct the examination.

"I hope they don't like to find fault with the doormen in the novel to collect the favor fee, otherwise we will have to work hard...... "For some reason, the scene of a group of doormen surrounding him begging for the favor fee suddenly flashed in his mind, throwing these inexplicable images out of his mind, and slowly walked to the guard of the gathering place who was checking the crowd with a scanner......

ps: I really want to collect and recommend...... In other words, the book review area is a bit deserted, and if you have any questions about the plot, you can mention it in the middle. The author will consider ノ(^u^)~yo.