It was a weird rustling sound, mixed with the sound of sand and gravel rubbing, and the sound of water splashing everywhere... No matter what kind of sound it was, it was obviously suppressed deliberately, and it sounded extremely weird .

Noticing the sudden and abnormal sound, Lei Xiao and all the subordinates who were on the march looked shocked and stopped in their tracks.

It has to be said that in this empty and spacious passage of an unfamiliar underground cave, this sudden and subtle sound is particularly eye-catching.

Immediately afterwards, Lei Xiao waved his hand to signal.

A group of people with awe-inspiring expressions began to slowly move to the right side of the passage, and quietly stood near the edge of the cave wall.

When they were moving forward, a group of people were walking on the right side in this huge underground passage.

Although a group of people are all wearing invisibility cloaks, which can be perfectly hidden visually, there is still a risk of being discovered by the opponent.

In this way, once a large troop of goblins passes by, they can quickly evade on the side of the cave wall, so as not to directly collide with the opponent's soldiers.

After all, the purpose of Lei Xiao's trip is not to completely wipe out this unknown number of goblin tribes, and to add more powerful enemies to himself.

Instead, it is much more convenient to look for Benson's traces and act in the dark than in the open.

"When I was at the City Lord's Mansion just now, even though the lieutenant general who received him tried his best to make everything look normal, when he mentioned Benson, the worried expression on his face was beyond words."

Nodding his head thoughtfully, Lei Xiao continued to think: "This place is not very far from Luolong City. If it's purely for reconnaissance, it's really unusual to not return for three days."

"It can be seen from this that the "Skull Crushing Madman" is likely to have encountered some kind of unexpected incident. "

Thinking of this in his heart, Lei Xiao brought his thoughts back to reality.

In addition to finding Benson, there is another thorny problem he is facing now: that is the sudden weird sound.

At this time, Lei Xiao, who was surrounded by his subordinates, noticed further.

Except for the ethereal dripping sound of water flowing down from the cave wall that is close at hand behind him.

The sudden rustling sound began to become more obvious and clear.

This means that the source of the sound is slowly approaching the group of people on their side.

However, even with the night vision effect of "Pupil of the Stars", there is still nothing in front of Lei Xiao.

This undoubtedly shows that the opponent, like his own, is also in an invisible state.

Realizing this, the subordinates beside Lei Xiao couldn't help but start to look at each other.

This sudden situation had obviously never been encountered before.

At the same time, a big question mark couldn't help but flooded the hearts of everyone present: "What is the sound?"

"I have to say that in such an already weird environment, there are weird sounds that cannot be seen from the source. It's really icing on the cake, and it makes people feel a little hairy."

In the pitch-black tunnel passage, Lei Xiao looked at the dark green crystals inlaid on the cave wall around him, emitting little green light, and couldn't help curling his lips slightly.

Next, Lei Xiao shook his head lightly to get these negative emotions out of his mind, and his face became serious again.

I saw that he first raised his index finger and put it in front of his lips to signal the subordinates to wait and see what happened.

Then, his gaze shifted, and first he exchanged a glance with Hu Zhang and Hong Ye.

From the solemn eyes of the two, Lei Xiao got a response, that is, in terms of energy fluctuations and aura, the two of them obviously didn't notice any clues.

Or in other words, there was no energy fluctuation from the invisible source of the weird sound.

Immediately afterwards, Lei Xiao looked at Bai Wei again, who lowered her brows and shook her head helplessly.

This means that, in terms of smell, there is also no gain.

In the end, Lei Xiao lowered his head slightly, and set his gaze on the small and exquisite Nan Xing and Nan Yue sisters.

The twin sisters understood, and pointed to their insteps with their slender fingers.

At this point, the answer is pretty obvious.

The sudden rustling sound seemed to be the sound of footsteps.

"Footsteps? Could it be that the other party is also wearing illusion equipment similar to an invisibility cloak?"

Just when Lei Xiao was in doubt, the suspicious sound of rustling footsteps was already very close to him.

At this time, Lei Xiao signaled his subordinates to be ready for battle at any time, while holding his breath, he pricked up his ears and listened carefully.

From the analysis of the slightly messy voice, the other party who is also invisible is not a single person, nor can it be a myriad of monsters. The number of people is obviously plural.

The sound of gravel rubbing is made when the soles of the feet or soles come into contact with the ground.

The sound of water droplets splashing was made by stepping on the small puddles formed by the water droplets seeping and dripping from the wall.

"So that's it. Is it really the sound of footsteps?"

Realizing this, Lei Xiao nodded slightly.

Immediately, an irrepressible doubt flooded Lei Xiao's cheeks again.

"If that's the case, then why is there no energy fluctuation, breath, or smell? Could it be some kind of special magical beast that is good at hiding its whereabouts? Or, could it be that the opponent's strength is higher than that of the knotweed and the red night?!"

"However, even if you can't perceive energy fluctuations, how can you be flawless in smell? You know, in terms of smell alone, the snow wolf clan, which is rare in number, is an extremely famous existence even on the entire continent. .”

Thinking of this, the puzzled expression on Lei Xiao's face became more and more obvious.

At the same time, Lei Xiao noticed further.

The source of the footsteps of the other party and others is directly opposite to our own side, located on the left side of the tunnel passage.

Moreover, judging from the sound of the other party's chaotic but regular steps, it seems that they have not discovered their own existence.

In addition, because the ground in the cave is hard, very similar to concrete ground, it is impossible to tell the clues from the footprints.

This, to a certain extent, hides Lei Xiao and his party, and naturally also hides the other party.

"What is the background of the other party? If the strength of the other party is higher than that of the knotweed and the red night, they must be able to see the flaws in the invisibility cloak."

"Thus, since the other party didn't see their own flaws, which means that the other party's strength has not reached the fifth level, then why can't the two of them, Hu Zhang and Hong Ye, also be unable to perceive the energy fluctuations of the other party? This point is simply unbelievable. "

While Lei Xiao was thinking, the rustling footsteps ~lightnovelpub.net~ had gradually moved away from the group of people until they completely disappeared in the distance of the passageway from which they came.

"Forget it, since the other party has already left, let's move on. Benson's whereabouts are currently unknown, so let's find this guy first."

After making up his mind, Lei Xiao immediately contacted A Ling and A Bing, who were guarding outside the cave, and reminded them to be vigilant.

Of course, in this case, Lei Xiao didn't directly remind him.

Instead, after connecting to read for a while, he took the initiative to hang up. This is the way Lei Xiao and his subordinates agreed to remind each other when it is inconvenient to make a sound.

After finishing everything, Lei Xiao nodded to his subordinates and made a gesture to move on.

However, a group of people just walked not far.

The unexpected happened again.

The rustling footsteps that had completely disappeared behind the group of people unexpectedly came from the front again.