According to the analysis, Ryan and the others believe that the ancient Laputans should have accidentally discovered the method of making flying stone crystals, and then created a thriving civilization based on the flying stone crystals.

However, because of the mismatch in the level of technology, there were many problems after the establishment of the floating city, and in the end, the Laputians had to give up the floating city and choose to return to live on the ground.

One of the most important is the problem of magic energy radiation, just like Ryan analyzed before, the ancient Laputa people's utilization rate of floating stone crystalline energy is extremely low, so a large amount of magic energy is released into the surrounding environment in vain.

This kind of high-intensity magical energy is quite harmful to the Laputans who are unable to master magic, and for those who live in the Floating City, they will find that if they stay in the Sky City for too long, their bodies will have some malignant lesions, especially for the next generation born in the Floating City, because they receive more radiation, so the malignant lesions on the body will become more and more serious.

In the end, unable to solve these problems, the Laputans had no choice but to abandon the Floating City of their wisdom and return it to the ground, while consciously blocking all the technologies of the Sky City and the Flying Stone Crystal, in order to prevent future generations from repeating the mistakes of the past.

However, like the life around Chernobyl, this radiation can cause damage to humans, but it does not harm plants, and even promotes the evolution of plants. The small ecological circle like a primeval jungle on the upper floor of Sky Castle and the huge tree that have no friends are very illustrative of this problem.

In addition, after the tree wrapped the fast flying stone crystals with its roots, a part of the energy was filtered by the tree to the upper layer of the sky city of Laputa, nourishing the growth of all things in the upper layer. This is the most important reason why the small and imperfect ecosystem at the top can last for a long 700 years.

After Ryan told everyone what he had analyzed, the entire main control room fell silent. It took several minutes for Hilda to wake up from the shock of receiving the news.

"Now I understand why Laputa perished. "In the valley of my hometown of Kendeya, an old song has been popular for 700 years. Its lyrics are sung like this, the roots should be rooted in the soil, survive with the wind, survive the winter with the bamboo, and sing the praises of spring with the birds. I think this is the warning of our ancestors to future generations. ”

"You're right, it's like this big tree has pointed us to a great direction for Sky City. Ryan gently patted the root of a tree that was thicker than himself and said, "High-intensity magic energy will indeed hurt people nearby, but the magic energy filtered by this big tree will not only not harm the surrounding creatures, but will even promote the benign evolution of the surrounding creatures." ”

"Yes, it is. Hermione nodded and added that she had discovered a little secret in the special energy cycle formed by a huge flying stone crystal and the big tree through her own methods. "I think that if you had adopted the plant filtration scheme from the beginning, 700 years would have been enough for you to evolve from generation to generation and finally master the power of magic. ”

As she said this, Hermione thought about the difference between wizards and Muggles in her home world. She now has enough evidence to prove that the ancestors of wizards and many magical creatures coincidentally lived in some kind of magical environment, and then evolved the ability to use magic and passed it down through genes from generation to generation.

Even Hermione suspected at this time that the ancestors of those goblins, giants or meeks were actually humans, but they had been affected by a different magical radiation than the wizarding ancestors. This would explain why, although they are far from humans in appearance, they are not reproductively isolated from humans.

Of course, it is better to do these important research topics in your free time. Now they need to find a way to hide the city in the sky.

"At least Laputa's own power can't hide the city. Ryan and Hermione were busy for five or six hours, and it wasn't until the evening came that they said helplessly to the two little ones who were already leaning together and almost asleep.

"Didn't we see a huge storm around this city in the sky before we came?" asked Baru, a little puzzled. "Wouldn't it be okay to re-summon that storm. ”

"If only it were that simple. Ryan said helplessly. "You know, the energy and difficulty required to re-start a storm in a calm sky is completely different from the amount of energy and difficulty required to sustain a storm, and now that many of the systems in Sky City have been damaged, once the storm is re-rolled up, we basically can't control the size and direction of the storm, in case that storm turns to land-"

"You're right. Hilda nodded. "Even if all the mechanisms on the way in we were able to operate normally, but considering that such a thick tree root could reach this space that should have been sealed, this city in the sky should be a big change from 700 years ago. I believe that in places where we can't see, a lot of things may not work as properly as they used to. ”

"Just now we found out that the weapon system of the entire Sky City can operate normally, as the core of the ancient civilization Floating City, the overall state of those purely military systems in Laputa is much better than other systems. For example, now we can use the city to shoot devastating lightning or manipulate nearly 10,000 war robots to sweep everything around us. Hermione said, spreading her hands. "But it doesn't mean anything to us, because it's enough for a flying battleship to destroy just our ship, and no amount of force means anything to us right now. ”

"So what do we do now?" Baloo crouched down in frustration, scratching his hair with both hands. "There is not enough time to hide this city in the sky with magic, and the city itself is not strong enough to hide itself as it used to be. ”

"Brother Ryan, Sister Hermione. Hilda suddenly stood up and looked at Ryan and said, "Did you say before that you have your own country in other worlds?"

"yes. Ryan nodded, "To be precise, we have our own countries in several worlds. It's just that all countries are not very peaceful, and they are always facing wars of one kind or another—"

After saying that, he and Hermione briefly introduced a few worlds one by one, and finally concluded: "So we are looking for information here and there, and that is to hope that we can obtain enough technology to defeat those enemies and make a better life for those who follow us because they believe." ”

"That's right!" Hilda nodded, and suddenly said something surprising. "So can you bring this city in the sky to your world?"

"What?" Baloo turned to look at Hilda in surprise. "Why?"

"It's simple. "On the one hand, there is no way to hide Laputa for the time being, once this flying city falls into the hands of careerists, then our world will be filled with blood and flames, and peace will be gone forever." ”

"On the other hand, even if we hide Laputa this time, with the development of flying technology, I believe that one day we will still discover this floating city. In this case, the only way to ensure safety is to hide the castle in the sky to another world. ”

"Well, I think we can hide this city in the sky to other worlds. But what are you going to do then?" Ryan asked now, a little worried. "After all, now that your identity has been revealed, unless you can hide in a place where no one is around, the careerists will always hunt you down. ”