This is why he could hear sounds that should be inaudible to human ears no matter how loud they were!

The conditions and symptoms they just experienced are basically consistent with the hazards of infrasound.

Infrasound of a certain intensity can stimulate the human nervous system, causing fear, mania, dizziness, nausea, vomiting, difficulty swallowing, loss of appetite, fatigue, weakness, dizziness, and tinnitus.

Moreover, infrasound waves of certain frequencies are similar to or even identical to the vibration frequencies of human organs, and can easily resonate with human organs, causing great harm to the human body. In dangerous cases, they can even cause death!

At the same time, infrasound waves have a low frequency, decay very slowly, and have a long wavelength, so they can diffract around certain large buildings. Some infrasound waves can even circle the earth for several weeks.

On Earth, sonic weapons are made based on the principle of infrasound.

This is a very scary sound that can kill people without them even noticing.

Unexpectedly, this big soft thing under the prison, just the sound it makes, is a deadly weapon, and can pose such a huge threat to them!

"So, what's going on, Brother Xin?" Zhao Xiaochuan's expression brightened slightly. "It's not just us. Those bugs outside are acting strangely too, huddled in the corners, not moving at all. Even those giant beasts are lying motionless on the ground, as if they're afraid of something."

"I was just careless."

Xu Xin rubbed Coco's little head, who was still shivering in his arms.

The behavior of the underground creatures in the prison coincided with his guess.

If the sound just now was that of a giant beast, then it is normal for these underground creatures to look frightened.

They were imprisoned and unable to escape, so they could do nothing but tremble and pretend to be dead.

At this time, Wen Guixin and Wang Lei also arrived.

"What happened?"

"Xu Xin, did you touch a button? Hey, why is the screen on?"

The two walked into the control room and saw the screen turned on at a glance.

Wen Guixin immediately walked over to the screen and examined it, then turned to Xu Xin and asked, "So, what button did you just press? I almost thought this prison was about to be launched like a rocket, and I was stunned by the rocket!"

The two men's faces were also a little pale. After all, they were also affected by the infrasonic attacks just now.

Although they cannot hear the sound, these impacts are real.

Fortunately, the people present were not ordinary people and the metal prison also blocked most of the sounds, so the few seemingly angry shouts just now did not have much impact on the people present.

After recovering, I just felt a little uncomfortable.

"Let's go out and take a look. I'll tell you as we go."

When they walked out of the passage and looked down at the soft ground outside, Xu Xin had already explained to them what had just happened.

"In other words..." Wen Guixin pointed at the soft ground below and said in disbelief, "The reason for the vibration just now, and the reason why we are uncomfortable, is all because of this big guy down there!"

"Isn't this... a little scary...?" Wang Lei stared at the soft ground below and swallowed.

"Just the screaming makes us... so uncomfortable? Moreover, we are still in the prison. If we were outside and were directly attacked by sound waves..." Zhao Xiaochuan couldn't imagine it.

The ground below outside had returned to calm at this time, and it was completely invisible that the ground had just deformed and opened a "big mouth".

The four of them looked at each other.

They still haven't figured out what they are going to do, but the dangers are becoming clear one after another.

This place is too dangerous!

As expected of a facility from the underground world...

"Hmm..." Keke finally recovered. She raised her head from Xu Xin's arms, glanced at the ground below, and buried her head again, muffled and crying, "Hmm!"

Coco probably knew from the beginning that this was the roar of the giant beast.

etc……

If it's a cry...

Maybe it contains some meaning?

"Coco!" Xu Xin held Coco in front of him.

"Hmm?!" Coco was startled when she was suddenly lifted up.

Feeling insecure being held up, it immediately started struggling: "Boo-boo-boo!"

"Keke, could you hear that cry just now? Does it have any meaning?" Xu Xin asked, staring into Keke's eyes.

But if it was possible to understand the words of other creatures, then if that voice just now contained some meaning...

Coco stopped struggling, wagging her big tail twice, blinking twice, and nodded her little head: "Bing!"

I can actually understand it!