[Underworld Ecosystem Level 4 (Special Skills): Establish an underworld ecosystem dedicated to the underworld city, cultivate special creatures that can live in the underworld, special upgrade methods, you can't use experience upgrades, upgrades need to form a complete ecosystem in an underworld, and slowly integrate the underworld into the real world]

[Note 1: Since the Underworld Biosphere skill is forcibly used to improve by breaking the rules, and the requirements of the ecosystem have not yet been met, the transcendent effect has not been activated, and the transcendent effect will only be activated if the various requirements required for level 2 to level 3 and level 3 to level 4 are completed.] 】

[Note 2: Due to the incomplete breakthrough of the Underworld Biosphere skill, the channel for upgrading from level 4 to level 5 will be temporarily blocked, and even if you complete the level 4 upgrade requirements, you will not be able to upgrade to level 5]

[Note: Even if someone can break the rules temporarily, the rules are the rules, and it is not always possible to do so.] 】

Looking at the information in front of him, Ryuji knew that things would not be so simple, and it seemed that this thing could not be used at will.

After thinking about it for a while, Ryuji wrote down the situation here, summoned a team of undead, and asked them to send a letter to Sandru, ready to tell Sandru about the situation here.

However, Liu Zhi never thought that in order to be simple, he originally recruited ordinary troops with no combat power, anyway, their existence did not affect the battle situation, even if there was no battle flag for them in the end, for the situation on Liu Zhi's side.

But as a result, when this army came over, it actually sent a huge surprise to Liuzhi.

This force was one of the Walled Legions that defended the city, but when they appeared, they became a coolie legion, carrying a huge chest behind them, and a strange-looking object was piled on top of it.

Before Ryuji could react, one of the undead sent a letter to Ryuji.

"Get excited, my master, I didn't waste your investment in vain, I have already made the lightning detonator you got last time, I named him the lightning automatic detonator, what do you think, this thing is very useful, it can automatically attract thunder and lightning in the sky and convert it into energy.

Of course, after the transformation, there may be a small explosion, and believe me, this explosion is not very powerful.

In addition, the main power source you sent over last time has also been modified, and I can guarantee that this thing will never explode, as long as you meet the following requirements when you install it.

In addition, I will send the installation drawings, which is very simple, as long as you find a platform to put this thing on.

By the way, my lord, for the sake of my efforts, let me study the machine that can let the wind out, and I promise that it will never break it. ”

Looking at the letter, which was obviously written by a black glove, Liu Zhi glanced at the box and a machine again, and Liu Zhi didn't know what to say.

This thing is clearly a problem for itself.

But after thinking about it, Ryuji thought of another thing, and during this time, he actually didn't forget the matter of Battleship Island that he thought of at the beginning.

These two things were sent to him, but they showed him a new way.

After thinking about it for a while, Liu Zhi kept these two things, and at the same time, some of his original plans were about to be expanded.

After sending the undead away, Ryuji took out a drawing and sat down near the Ancient Tree of Life.

At this time, the elven mage also ran over and said very politely: "Master, is it time to start building ships?" ”

"Okay, I'll calculate the materials I need first, you just need a legendary elf ship, right?"

The elven mage looked at Ryuji inexplicably, how many boats was he planning to build?

However, he soon discovers that Ryuji's calculations are expanding, and from the data in his hands, it can be seen that Ryuji does not only intend to build a legendary elven ship.

This time, Liu Zhi directly ordered his subordinates to go over together and helped cut down ten big trees, saying that they were to be used for shipbuilding.

This scared the elven mage.

You must know that the big trees on this planet are not like ordinary planets, the highest is only more than 100 meters, and all the trees that can be called big trees here are giant trees of more than 1000 meters.

Liu Zhi only put down one tree before, and then built five elf boats, and this time he put down ten trees, which is going to turn the sky upside down.

But Ryuji didn't care, he was now a legendary shipbuilder, and he could design the ship himself, and there were too many things that Ryuji couldn't handle in the previous battleship island so he failed.

But now it's different, where it failed at the beginning, now Liu Zhi can handle it all well.

So Liu Zhi had another idea in his heart to build Battleship Island.

And this time, he was full of confidence in his heart, as if he could build Battleship Island if he wanted to.

This time, Ryuji plans to build seven ships at the same time, in addition to the elven sailboat promised to the elven mage, Ryuji plans to build two solar ships, two magic transformation three-masted ships, plus two elven sailboats.

All the ships Yanagi planned to build the Legend class, and then use the plant continent to piece together these Legend class ships and turn them into a battleship island composed of many warships.

And the biggest problem in this plan has actually been solved.

That's the question of the power of the entire battleship island.

If it's just an ordinary ship, the sails are actually enough, but what Yanagi wants to do now is the battleship island, and if the six ships want to drive a huge island, this power is definitely insufficient.

Ryuji was stuck on this in the first place, and he wasted too much time here.

It's different now, the main power source that has just been sent by the black glove is a good source of power.

Ryuji only needs to place the main power source on Battleship Island to activate the effect of Battleship Island.

As for what level Battleship Island will be in the end, Ryuji is not worried about this, he believes that the entire Battleship Island is supported by six Legendary-level battleships, and that level will definitely reach the Legendary-level level.

Liu Zhi thought of something and immediately started to do it, of course, because his shipbuilding skills had improved at this time, many things did not require him to care too much.

He can delegate some of the heavy lifting to his clones, such as chopping wood, etc.

Sometimes the elven mage will also come to help Yanagi, this elven mage has no other skills, but it is still easy to operate spells.

With his help, the speed of ship construction was significantly increased.

Three days later, when Ryuji saw a steady stream of Imperial troops coming, Ryuji's ship was almost finished.