Cui Si continued to pile up the materials, and then the yellow-robed monster saw the tens of thousands of zhang high Xuantie Mountains appear continuously, and soon filled the open space within a radius of hundreds of miles.

Then Cui Si said with satisfaction: "These are almost enough to start construction, and the remaining materials will be sent one after another in a few days, please rest assured!" ”

"Good, good!" The yellow-robed monster is almost so happy that he doesn't know how to talk except for saying yes now.

Subsequently, the excited yellow-robed monster respectfully invited Cui Si, the rich man, back to Gou Chen Palace, entertained him in a high-end hotel, and sent the most beautiful flying fairy to serve him, for fear of neglecting him.

After settling Cui Si, the yellow-robed monster happily ran to Emperor Gou Chen and told him about the situation. Emperor Gou Chen was excited, and immediately ordered his subordinates to receive the materials, and then build according to the city defense drawings provided by Cui Si.

Don't look at the time when you were in the Four Seas Dragon Realm, it took more than a year to build a thousand miles of city defense, and people didn't need Yu Chentian. After all, the manpower and material resources here are extremely sufficient, and there are many masters here, whether it is casting walls or carving formations, they are much faster than Cui Si's subordinates.

So the situation here is not at all comparable to Cui Si at the beginning. Cui Si estimated that in only three months at most, people could build 20 thousands of miles of city defenses at the same time.

The only thing missing now is the dragon cannon. You must know that according to the calculation of the most dense arrangement, on average, on the ten miles of city defense, it is necessary to install 100 giant dragon pattern cannons, and the city defense of 10,000 miles is as many as one million.

And now if Emperor Gou Chen wants to build 20 thousand miles of city defenses, he will need a full 2,000 giant dragon cannons. Not only that, but the defensive strength of other places in Yu Chentian must also be enriched with dragon pattern cannons, so many small cities add up, which is also a large number, so calculated, it is difficult to deal with it without forty or fifty million dragon pattern cannons.

However, Cui Si tried his best, but he could only immediately come up with seven or eight million dragon pattern cannons, many of which were medium-sized and used by his own fleet, rather than the giant dragon cannons dedicated to city defense.

This gap is really big, Cui Si had to quickly send people back to let the craftsmen of the Four Seas Dragon Realm speed up production, and at the same time, his own flower demons also stopped making low-level five-spell flying boats and turned to manufacturing dragon pattern cannons.

Of course, Cui Si would not use all his strength on refining the Dragon Pattern Cannon, because he also had important things to do, that is, refining the Sun Divine Boat. Since obtaining those nine high-grade immortal artifacts refined by the Sun True Fire, Cui Si is equivalent to having nine cores and can continue to produce the Sun Flying Boat.

However, the power of these nine immortal weapons is different, and the principles in them are also slightly different, so if they are used as the core, the five magic flying boats produced must also be different.

Therefore, Cui Si set aside a large part of the flower demon craftsmen to design and manufacture flying boats for the core of these nine immortal weapons. To that end, he had put all other ship-building on hold and let all nine of them start at the same time.

As long as these nine super flying boats joined, the strength of Cui Si's fleet would increase several times out of thin air, because the power of any one of them was enough to be worth dozens of ordinary flying boats of five thousand zhang.

So, in the following time, Cui Si and Emperor Gou Chen were both working hard to produce, one to make the Sun Shenzhou, and the other to make the city defense.

At this time, the entire Jade Chentian was about to turn into a giant construction site, and a large amount of materials were continuously transported from the Eastern Emperor Realm. It was so busy that everyone in Yuchentian couldn't stand.

However, although everyone was busy to death, they were very happy in their hearts. They have experienced countless cruel wars, but they are all understanding people, and they know that sweating more at this time can shed less blood when the war comes, so everyone's enthusiasm is very high.

Yu Chentian was building so many large-scale projects at the same time, of course it was impossible for the demon clan army on the opposite side not to know, although they didn't know what kind of medicine was sold in Emperor Chen's gourd, but they subconsciously felt that there must be a conspiracy in this.

The demon race is not a race that likes to sit back and wait, on the contrary, they are fierce by nature and like to take the initiative to attack the most. As soon as they realized something was wrong, they launched a small-scale harassment.

Thousands of small teams were sent to Yu Chentian, they were all composed of the elite of the demon clan, each team was not a few people, only a dozen, but it was extremely difficult. Not only is it tough, but it's also particularly cunning.

They didn't come to fight Yu Chentian for a decisive battle, the purpose was just to spy on intelligence so that they could understand the purpose of these big projects. Therefore, these guys all infiltrated Yu Chentian's hinterland with a sneaking situation.

It was not the first time that the demon clan had used this kind of ghost trick, so after Emperor Gou Chen got the report, he immediately took countermeasures, and a large number of purging troops were also dispatched. The two sides soon engaged in a fierce battle in the wilderness of Yu Chentian.

Perhaps this kind of small-scale battle is not as fierce as the great war where millions of men and horses are entangled, but the tragedy is even greater. Both sides are buying time, so once they meet, they will release their strongest firepower at the first time, and even break out in the form of self-harm.

Therefore, often the time of this kind of battle is very short, but once it is encountered, it will inevitably end in the complete destruction of one side, and the victorious side is not comfortable, and often suffers heavy losses under the opponent's death-defying blow, and even many times, the two squads die together, and there is no winner.

Of course, as the home battle, the Yuchen Tianyi series still has to take advantage, they are familiar with the terrain, and it is a defensive battle, so they can set up an ambush, so they can often kill the opponent by surprise. So overall, they suffered much fewer casualties.

But the demon clan is not a vegetarian, and the people who can come here are definitely the masters of the masters, so even if they are ambushed, they can often cause losses to the ambushed Yu Chentian troops.

Moreover, the main purpose of the demon clan troops is not to kill people, but to spy on intelligence. With so many squads to cover, the strongest elite squads hidden in them can often fish in troubled waters and find what they need.

As a result, after more than a month of fierce fighting, the demon clan threw down hundreds of thousands of corpses and retreated, while Yu Chentian's side also suffered more than 100,000 casualties.

Although on the surface, Yu Chentian had achieved an absolute advantage, but in fact it was not, because they found that many immortals who were responsible for building the defense of the city were missing.