The star of the wilderness.

A tent stands here at the edge of the basin formed by the self-destruction of the red lotus.

A cable shook out from the gap in the tent and stretched into the basin and disappeared into the inconspicuous cave.

The second exploration robot was parked by the tent, quietly waiting for the order to set off.

Some noisy arguments came out of the tent.

"…This thing is definitely not an arrow!"

"What's it if it's not an arrow?"

"I don't know... It's definitely not an arrow anyway! It's also impossible!"

"What evidence do you have?"

"I... definitely not anyway!"

"Hmph, you can of course say nothing without evidence!"

“…”

In the tent, the researchers under the man with glasses were divided into two camps and were discussing fiercely.

One of them believed that there was some kind of intelligent creature in the cave and attacked the exploration robot with a bow and arrow.

The other party believes that since it is recognized as a wild star, there is no smart creature, and there will be no smart creatures that use bows and arrows.

The reason for their beliefs is also very reasonable:

Although the exploration robot is simple, the materials used to make it are all high-quality steel with small inventory.

The bows and arrows that can shoot steel robots must be made by professionals enough, and professionals mean the formation of social division of labor, and social division of labor means a certain scale of civilization... and the existence of civilization will inevitably transform nature.

No matter how large or small the scale of such a transformation is, it is too simple to discover. Since the star pirates divided this place into a deserted star, they must have found no signs of civilization.

However, the other side believes that the civilization on the wild star must be hidden underground. The star pirates are not disciplined and professional, so it is easy to ignore the traces of civilization hidden deeper.

Neither of the two sides could convince each other, and the debate gradually became louder.

"I don't know if there is any civilization in the cave, but that thing should not be an arrow." Chen Zheng said as he looked at the frozen video, "If it is an arrow, at most one or two instruments will be shot, and the entire exploration robot will not lose all signals in an instant."

"Maybe... the arrow shot the cable off?" a researcher guessed unwillingly.

"Impossible." Chen Zheng pointed to the spare Explorer No. 3 in the tent and said, "The arrows were shot from this direction... and from this direction, they can only shoot the searchlights and cameras, and at most they can destroy the infrared probes and ultrasonic generators. It is absolutely impossible to shoot the cable reel system behind them."

Through Chen Zheng's deduction with real objects, everyone agreed with Chen Zheng's point of view.

Next, the verification time.

In order to see clearly what happened on Explorer One, after a simple modification, welded the wedge-shaped front armor and full-cover iron armor, and moved the position of the infrared detector, the brand new Explorer Two embarked on the journey.

Moving along the cables on the ground, Chen Zheng and others stared at the screen... As they got closer and closer to the place where Explorer One lost contact, the atmosphere in the tent gradually became tense.

"Guru..."

The researcher in charge of controlling the power system swallowed, rubbed his hands on his thighs, and looked at the screen with all his energy, as if he was on guard against a great enemy. Those who didn't know thought he was going to operate the robot to avoid bullets...

However, the purpose of the Explorer No. 123 robot was only to carry various sensors. The power of the motor was not high. Even if the lightweight Explorer No. 1 went long, it could only run 30 kilometers per hour.

Not to mention Explorer 2, after nearly 100 kilograms of armor were added out of thin air, even at the extreme speed, it could only move forward at a speed of 8 kilometers per hour, let alone dodging.

However, even though I knew this, as an operator who had lost Exploration No. 1, was still very nervous.

The light shines on the slowly retreating hole wall.

All the breathing sounds remained in the tent.

It was not until this time that Chen Zheng realized that there was actually something wrong with their preparation. Although the sensors on the Explorer robot were very rich, there was no audio collection device. No wonder he always felt that something was missing before, but it turned out that there was no sound.

Just as Chen Zheng was thinking this way, the back of Explorer One suddenly appeared on the screen.

From the back, as Chen Zheng said, there was no problem with the cable retracting and retracting system, and all the cables were rolled intact on the reel.

However, when Explorer 2 went around to the front of No. 1, everyone staring at the screen took a breath!

I saw that the front of No. 1 seemed to be sprinkled with sulfuric acid, and all detectors, cables and even metal frames were corroded to the point. The position of the central motor of No. 1's chassis became a big pit, and a pool of dark green liquid was slowly smoking.

"What is that? Wang Shui?" Chen Zheng looked at the picture incredibly.

Aqua regia is one of the most corrosive acidic substances on the earth, and its main components are concentrated hydrochloric acid and concentrated nitric acid.

However, even the Aquarius cannot corrode several different metals into this in a short period of time - Chen Zheng even saw that the glass covered on the video probe was corroded! This is something that even Aquarius cannot do!

"...You are right, that thing is indeed not an arrow." The man in glasses frowned deeply.

"...Can you analyze what solution it is?" Chen Zheng asked.

"It's hard to have no samples." The man in glasses shook his head. Although Explorer 2 has undergone a lot of modifications, it does not carry a robotic arm, so naturally it cannot take samples or drag No. 1 back.

"But... in my experience, it might be some kind of organic acid." The man in glasses thought about it and said.

"Organic acid?" Chen Zheng's understanding of chemistry was limited to high school textbooks, and he had almost never been exposed to relevant knowledge after college.

"Most of the common organic acids are weak acids, but I have heard before that some organisms' gastric juice may show acidity beyond strong acids... I thought those are rumors."

"Increase the power and see how big it is around first." Chen Zheng waved his hand and interrupted the man with glasses.

“Yes, increase the power…”

As the power of the ultrasonic generator becomes larger and larger, the receiver gradually receives some echoes, and the terrain of the entire space becomes clearer.

For the time being, the detected space is in a horn shape. Even if the power is increased to the limit, there is still no sign of closing the opening of the horn... This shows that the underground space is beyond imagination.
Chapter completed!