In the dim darkness of space, a gray-white irregular asteroid floats.

This asteroid is large and small, more than 500 kilometers long, and 380 kilometers wide at its widest point.

This is where the Grain Boundary Stone Cave is located.

Zhang Yuan turned on the Night Walker system and quietly wandered above the asteroid, this asteroid was so huge that the Grain Boundary Quarry was only a small part of it, and most of its surface still maintained its original appearance, with no traces of human involvement.

After going around a few times, Zhang Yuan had a general understanding of the asteroid's defenses: "There are 16 rapid-fire cannons around the mine to form a hunter system, there is an ultra-high-energy barrier at the entrance of the main mining area, there are at least 50 different operating noises in the mine, and at least 50 mecha warriors are defending...... It is not difficult to sneak into this mine, but once you are discovered, it will be difficult to get out again. ”

Thinking about it, Mi Xiu also knew that he couldn't resist Zhang Yuan's invasion, so he adopted such a strategy of 'inviting you into the urn'.

If he guessed correctly, once he alarmed the defense system, Mi Xiu should be in a very short time to come to the rescue.

At that time, he was sealed in the mine by the ultra-high-energy barrier, and there was no way out, so he could only fight Mi Xiu.

Eventually, Zhang Yuan stopped 5 kilometers outside the entrance of the mine, and he looked at the spacious entrance of the cave from a distance, and fell into deep thought.

"What can be done to minimize the risk?"

It will definitely not be possible to break in like this, and he will have one life, if he keeps taking such risks to find death, it is really possible to make a mistake one day.

After thinking for a few seconds, Zhang Yuan took out a mecha that was only more than a person tall from the space folding bracelet.

This is a miniature mecha, equipped with a rhodium magnetic remote control system, this mecha is tiny, weighs no more than 200kg, and the power output is only less than 400 horsepower, which has low material requirements and is simple to build.

When Zhang Yuan was building the lava rhodium magnetic engine, he sometimes encountered some problems, so at this time, he built a miniature mecha to pass the time, and sorted out his thoughts by the way.

Suffice it to say, this mech has little destructive power, and the only outstanding performance on the mech is concealment.

Zhang Yuan has put a lot of effort into stealth technology, and he has developed several generations of new stealth technology on the Earth Mecha's Nightcrawler system, and it has now reached the fifth generation of Nightcrawler.

This miniature mecha is loaded with five generations of Nightcrawlers, exactly the same stealth system as the White Angel. Suffice it to say, if this miniature mecha can't break through the defenses, then the White Angel can't pass quietly.

"Mecha Launch...... Open the Twin Coupling System. ”

"Zi~Zi~"

The miniature mecha sounded a few times, and then moved in place, its movements were exactly the same as the white angel that Zhang Yuan was currently driving.

"That's it!"

Zhang Yuan looked left and right, and scanned a high-density area about 10 kilometers behind him, which has excellent signal shielding ability, except for rhodium magnetic signals, others are basically impenetrable.

"Good place."

Zhang Yuan went all the way, and when he walked in, he found that this was an abandoned mine, only about 20 meters deep, and there were many low-quality grain boundary stones on the four walls of the cave, thinking that this should be the reason for signal shielding.

Manipulating the White Angel mecha to hide in the mine, turn on the Night Walker system, and then switch the control mode to the simulated virtual cabin mode, and the perspective of the white angel's internal surround holographic screen switches to the miniature mecha.

The current situation is that he uses the White Angel as a remote control cabin, driving a miniature mecha into the Grain Boundary Stone Mine Cave to investigate the situation, even if it is really accidentally discovered, he is at most sacrificing a mecha that he has built casually, which is insignificant.

He carefully maneuvered the miniature mecha, not rushing forward, his eyes were glued to the mine scanning wave fed back by the miniature mecha.

The detection waves around the mine are very dense, and there are almost no dead spots for scanning, but there are many interference signals in the starry sky, especially when it is not too far from the star, and the signal interference is even more serious.

What Zhang Yuan had to do was to take advantage of the explosion of a large-scale cosmic signal to break through a distance.

This matter requires a lot of patience, and Zhang Yuan is the most lacking in this.

About half an hour later, a violent electromagnetic explosion caused by the eruption of a stellar flare arrived, and even the white angel holographic screen appeared with a slight ripple.

"Good chance!"

Zhang Yuan immediately manipulated the miniature mecha to run forward, and the path he ran on was also very particular, which was the weakest line of the detection wave.

'Zi~Zi~'

The peak of this wave of electromagnetic explosion lasted for about 5 seconds and began to fall, Zhang Yuan had already calculated the detection threshold of the other party, and when the electromagnetic explosion dropped to a certain level, he immediately stopped moving forward and waited patiently for the next opportunity.

Generally, a flare like this will last for an hour or two, and there will be several magnetic storms that break through the opponent's carrying limit in the middle, Zhang Yuan's luck is quite good, and about 11 minutes later, another wave of magnetic storms arrived.

After more than 3 hours of stop-and-go like this, Zhang Yuan finally arrived at the entrance of the Grain Boundary Stone Mine Cave, as long as he walked another 50 meters, it was where the ultra-high energy barrier was.

From the perspective of the miniature mecha, you can see a dark blue spherical force field, which wraps the hole tightly, and there are almost no flaws.

This force field is called an ultra-high-energy barrier because of the terrifying energy it contains. Once an object invades, this force field will penetrate the intruder in an instant, causing a super high temperature of more than 100,000 degrees in the object.

Such energy can destroy the structure of almost all matter that exists in the universe in an instant, without exception.

Of course, this is the result of confrontation with this force field, and if it is not confrontation, then it is a different matter.

It just so happens that Zhang Yuan has a way to penetrate the force field without causing a reaction in the force field, this is the quantum engine, which can make the physical existence become a quantum wave and quietly pass through this force field, the only disadvantage is that the quantum engine is extremely energy-intensive and cannot be used more.

"Start the quantum engine, the degree of quantization is 98.21%, lasts 1 microsecond, and the target coordinates are (11.21.98)."

"Executing command ......"

After an instant, there was an extremely brief trance on the holographic screen in front of Zhang Yuan, and after the image regained stability, the miniature mecha was already silently standing inside the ultra-high-energy barrier.

Inside the barrier is the entrance to the mine, which is very large in order to meet the needs of large transport ships, 200 meters high and 200 wide, facing such a huge entrance, the miniature mecha is like a small ant on the ground.

At the entrance of the mine, there are constantly transport ships flying in and out, and at the entrance on the edge of the mine, a large number of rapid-fire fortress cannons are arranged, and there are usually 1 or 2 mecha warriors standing around the muzzle, and in the entire mine space, a large number of miniature detection aircraft are arranged.

These miniature flying machines are densely packed in hidden corners that various mechs can't reach, leaving almost no dead ends.

"In order to protect this grain boundary stone mine, Mi Xiu really made a mistake." Zhang Yuan couldn't help but sigh.

However, there is no complete system in this universe, and the more complex the system, the more likely it is to have fatal flaws.

After standing on the edge of the ultra-high-energy barrier and observing for 5 minutes, Zhang Yuan found an interesting phenomenon.

He discovered that when the ship transporting the Grain Boundary Stone rushed out of the depths of the mine, a large number of high-energy jets appeared near the vents of the spacecraft engines, and in order to protect themselves, these miniature detection vehicles would avoid this jet 2 seconds in advance.

Then the question arises.

The destructive power of this jet was enough to easily destroy the micro-aircraft, but not enough to cause damage to Zhang Yuan's micro-mech, and at the same time, because the aircraft avoided it 2 seconds earlier, there was a time difference here.

For at least 2 seconds, there is a space in the interior of the cavern where there are neither jets nor miniature detection vehicles.

If you count the time for the aircraft to fly back and fill in the blank again, then, after a transport ship appears, Zhang Yuan will have at least 3.3 seconds of action time!

All these provided an opportunity for Zhang Yuan to sneak into the mine silently.

After discovering this flaw, Zhang Yuan did not rush to act, he stayed for another 2 hours, and in these 2 hours, he did two things, one was to count the transportation schedule of the transport spacecraft; The second is to observe the law of the flight trajectory of the miniature detection aircraft.

Two hours later, Zhang Yuan already had a grasp in his heart.

He took a deep breath, looked left and right at the mecha guards on both sides of the tunnel, and began to count silently in his heart: "9,8,7......6,5,4,2,1...... spacecraft has arrived!" ”

"Woo~" The low sound of the jet engine sounded, and a heavy iron-gray transport ship rushed out from the depths of the mine, with a translucent high-speed jet at its tail, and everywhere it passed, the detectors dodged to both sides like mosquitoes, and an obvious gap appeared.

"It's now!"

Zhang Yuan immediately used the maneuvering footwork of 'White Ape Leap', and the entire miniature mecha bounced abruptly, taking a few steps in the air, and with each step, a very inconspicuous air ripple appeared under the mecha's feet, which was an anti-gravity force field.

It flew through the air with a miniature mecha.

Three seconds later, with the help of the scanner, Zhang Yuan spotted a hole that appeared after the high-speed dodge of the detected aircraft and hid in.

After hiding inside, he silently said in his heart: '3, 2, 1, the spaceship has arrived!' ’

"Woo~" Another transport spaceship rushed out, and the gap reappeared, and the hole where Zhang Yuan was hiding just now was about to disappear.

Zhang Yuan immediately pulled away, and when he left, the nearest miniature flight detector was less than 5 centimeters away.

In this way, Zhang Yuan borrowed the gap 4 times in a row and successfully rushed forward 500 meters, at this time, a spacious square appeared in front of him, and a large number of intelligent robots were busy in the square, and they kept loading the grain boundary stone onto the transport spacecraft, without stopping for a moment.

There were so many moving objects in the square that the number of miniature detection robots in the air was greatly reduced, and it was no longer almost full of air as before.

When he arrived here, Zhang Yuan breathed a sigh of relief, found a corner to hide, and then began to observe carefully.

The loading dock is very wide, at least 300 meters high and more than 700 meters long and wide, and most of the work here is made up of intelligent robots, but there is an entrance sealed with transparent material on the stone wall on the left side of the loading area.

Through the transparent material, Zhang Yuan could see that there were figures walking inside, and from time to time mecha came and went, which should be the place where the mine security guards lived.

Zhang Yuan stayed where he was again and patiently observed.

This time, he waited for 5 hours, observing not only the transparent entrance, but also the whereabouts of the mining robots, the most important of which was the number of spirit primordial stones in the grain boundary stones that were transported back by the mining robots.

Five hours later, Zhang Yuan determined his whereabouts.

It was one of the three largest mines next to the loading and unloading area, and its location was on the left side of the mine's security area.

Let's put it this way, if there is a core area in this grain boundary stone, then this mine must be the closest passage to it.

However, Mi Xiu obviously thought so too, and the tight defenses he had placed in this mine road made Zhang Yuandu feel a little very tricky.

Not to mention the miniature detectors that are densely covered in the mines, the mine security guards will go to the mine every 10 minutes to patrol, and a large number of bayonets made of high-strength materials are also arranged inside the mines.

How do I get into this place?