All three of them could clearly feel that the ground beneath their feet was shaking slightly.

"The roots of the World Tree can also take root in the underground world..."

Xu Xin looked at the magnificent scenery in front of him, which he participated in creating, and said to himself.

"That's right, but it can't spread as well as above the ground." Xu Ying said with some pity, "After all, there is a soil-free area with a vertical distance of up to three thousand meters in the underground world. The roots of the World Tree can penetrate into the underground world like this.

The ground is almost at its limit."

"Can't the root system of the World Tree be able to extend to areas hundreds of kilometers away?" Li Wenxi felt the vibration under her feet, "Then if there was no such a hollow underground world underground, would its root system be able to extend all the way down?

?”

"I'm not sure about this, but judging from the situation above, it will at least be deeper."

Xu Ying looked up at the dome.

The intricate root system fills the dome above the people.

These root systems have emerged from the dome, and countless root systems are crawling all over the dome, as if telling their dissatisfaction.

"Huh? They are all over the world?" Xu Ying turned to look at her and said, "There shouldn't be any problem with this, right?"

Even if he eats a red berry, he still can't see very far away.

"Hehe, that's right! My brother can do it too."

From this point of view, perhaps all their survivors are in the "danger zone" that is not affected by the World Tree.

The... stepping stone of the Earth's crust?

Several giant insects on the ground were directly lifted away!

"Still smiling! You look so pale!" Li Wenxi supported Xu Xin and turned to look at Xu Ying, "Are you tired or injured?"

"You don't have to look around, there isn't one here." Xu Ying reminded, "That kind of 'support pillar', based on the distance on the ground, will only have one at least every two thousand kilometers."

"Successful!" Xu Xin's eyes flashed with shock. He turned to look at Xu Ying, "Can it also be done on the ground..."

From the ground to the underground world, it is much farther than three thousand meters.

He was excited, and another thick and sharp root came out of the ground!

"In that case... what is the ground supported by?" Li Wenxi stretched out her slender fingers and pointed upward.

"Two thousand kilometers? That's really far away..." Li Wenxi said in surprise, "If the earth hadn't gotten bigger, there wouldn't have been many roots on the entire earth, right?"

"But there is a distance of at least two thousand kilometers between those 'support pillars'." Xu Xin thought, "In other words... there is a large area between the two World Trees that is not affected by them.

of."

And they didn't have to do anything next, because the flag helped them occupy this area! They even occupied the underground world along with it!

This is really...

"Ah, you have to control yourself, brother!"

"Why should you be the farthest away from every support column?" Xu Xin was confused about this, "Going far away from the support columns?"

"Where are those giant beasts?" Xu Xin asked.

"It's not normal. But this place is affected by the World Tree." Xu Ying opened her eyes and looked at the main vine bundle at close range, and explained at the same time, "I'm teleporting in my own home, can something go wrong?"

In an instant, a thick root with a sharp head emerged from the ground!

These thick roots can probably cause considerable damage to giant beasts!

"Ah!" Li Wenxi was so shocked that her mouth grew wide, "You can control those roots!"

"It turned out to be like this..." Xu Xin whispered to herself.

They still want to drill down, but there is no soil, rock, etc. for them to drill down.

It is more appropriate to say that it is a "support pillar" than a "support plate".

Counting the roots that controlled the dome just now, he controlled the roots of the World Tree seven times in total.

"No need." Xu Xin took out a few blue-level fruits and ate them, "Just recover a little bit. Can we go over there and have a look now?"

The underground world is closer to the center of the earth. If you count the distance of the underground world, it is definitely shorter than 2,000 kilometers.

"And we are now in the opponent's 'danger zone', and we are also the core hinterland of the 'danger zone'. We chose to build Crystal City here because of its location."

Entered directly into the underground prison.

Xu Ying's explanation allowed the two of them to know a lot of details.

In any case, the current survivors should be considered relatively lucky, at least they are not under the control of the other party's World Tree.

"That's right!" Li Wenxi imagined the appearance of the support pillar, "If we plant the World Tree on the 'support pillar', wouldn't the root system of our World Tree be able to extend downward? Such a World Tree should be able to

Be stronger!"

"I'm just tired. My body is overstretched." Xu Ying was not worried, "Just take a rest and you'll be fine."

Saying that, Xu Ying waved her hand upward.

"And if a new tree is planted outside the 'protected area', based on the 'first come, first served' principle, the roots of the world tree planted later will not be able to spread here. At most, there will be two worlds.

The 'protected areas' of trees are connected."

No wonder the entire earth's crust and the above-ground world can be supported.

"Because those alien bastards mainly live on that half of the planet. It's the place where Shi Wanyun went."

"You just controlled the roots of the dome, and now you have controlled it twice in a row. You should have reached your limit, right? It's not that easy to control the World Tree. I have super mutated physical strength and more than three hundred years of mental strength.

, I already feel exhausted.”

At the beginning, Xu Ying was unable to teleport over a distance of three thousand meters from the ground to the dome in the underground world.

It was almost the same distance from the Imperial Capital to the Demonic Capital on Earth a thousand years ago.

"That's not the case." Xu Xin calculated, "The equator is more than 40,000 kilometers away. There are about twenty roots on the equator alone, and even more on the entire planet."

Li Wenxi also quickly supported him and said nervously: "What's wrong? Why suddenly..."

ah.

The feet were still shaking, but the giant beasts and insects on the ground were no longer as panicked as before. Instead, they calmed down and lay on the ground one by one, as if they were feeling something.

Xu Ying also quickly came over to support him.

Xu Xin was also in deep doubt at this time.

As she said this, she smiled: "In fact, you should be familiar with this. In fact, it is similar to your little tree house. The little tree house is a degraded version of the World Tree, and the properties of the two are basically the same.

"

Because the last time they left, this place was filled with giant insects and beasts.

This number of times is enough!

With that said, she directly grabbed their hands and teleported again.

Further away, it was pitch black.

"As far as I know, no." Xu Ying stood up and said, "As far as I know, the World Tree follows the principle of first come, first served. This area has been occupied by our World Tree, and other World Trees have even

It can no longer grow on this land, unless it is...'parasitic'. This is the 'protected area' of World Tree."

Xu Ying looked at this huge underground prison that spiraled downwards, secretly surprised in her heart.

Although physically exhausted, he was in a good mood.

"That's right." Xu Ying pursed her lips and said, "But, if we can think of this, how could the other party not think of it."

It's coming with force, sweeping over like a wave!

Because the World Tree will obviously affect the growth, belonging and transplantation of the small tree house.

Xu Ying pointed upward and said: "And this is the location we specially selected. It is far away from every 'support pillar', and the nearest support pillar is nearly a thousand kilometers away."

Xu Ying nodded: "Yes, that's it. The World Tree planted on the 'support pillar' will not only affect a large area on the ground, but the root system will also extend downward from the 'support pillar' and enter the ground.

The ground of the world continues to spread. In that case, with only one World Tree, they can easily control large areas of the surface world and the underground world."

A thick root burst out of the ground with his consciousness!

"Oh, this is the underground prison!"

They have already planted a world tree here!

With this World Tree, they have their own territory and the ability to compete with their opponents.

The three of them arrived at the main vine in an instant.

Xu Xin is already trying.

Xu Ying squatted down and touched the ground, feeling the increasingly faint vibrations under her feet, and said at the same time: "The underground world is so rich in resources, and the number of alien invaders is not large. They have no population pressure and no shortage of survival.

If you use research resources, there is no need to waste energy on expansion to occupy large areas of useless area.”

"Yes." Xu Ying nodded, "But when we built Crystal City, they basically didn't care about it."
To be continued...