Kai opens the base gate, and a wave of monsters rushes into the base.

The monster was quickly annihilated, but the gate did not close immediately.

Defensive platform, near the entrance to the passage.

Three forklift-turned-expedition vehicles lined up in a row, with their heads facing the entrance, their lights on and their engines humming.

Lu Wei opened the door of an expedition vehicle in the middle, put a quadcopter drone, a fully enclosed low-temperature protective suit, an oxygen backpack, convenient food, mineral water and other items into it, and then put on a set of protective clothing and sat on the driver's seat of the expedition vehicle.

The energy core used in the expedition vehicle is provided by Kai, each expedition vehicle is only equipped with one, and after the energy is exhausted, it will be replenished by the base, Lu Wei can't handle it, and he doesn't agree to bring two more as a backup, just saying that one energy core is enough, and there is no need to carry it extra, which seems a little unkind.

Lu Wei had to express his helplessness, hoping that when the number of tower defense bases increased in the future, his own energy cores would be inexhaustible, and when the time came, he would bring a few if he wanted to.

"Kai, I'm leaving, if there's any emergency, you have to find a way to come and help me, I don't want to go back forever." After putting on the protective clothing, Lu Wei said with some complaints.

"Understood, Wei, all expedition vehicles have signaling devices, if you have an accident, I will send an expedition vehicle to pick you up immediately."

The driving mode of the expedition vehicle is divided into two types: "manned" and "unmanned", the manned mode is controlled by Lu Wei, and the unmanned mode is controlled by radio, and the radio control range is very wide, that is, even if it is thousands of kilometers away, Kai can control the expedition vehicle and complete the task of support or rescue.

This will produce a certain amount of controversy, since the unmanned mode can also play a role in exploration, why not directly use the unmanned mode to find a place to place, how safe, and save the province of sending people out on adventures.

Having said that, some of the advantages of the manned mode are far inferior to the unmanned mode, which can collect more valuable information, make better judgments, and deal with various situations in a timely manner.

For example, if there is no one on the moon and someone on the moon on the earth, compare the meaning of the two, and I believe that anyone thinks that it is better for someone to go to the moon.

"Okay, Kai, then I'll be relieved, I'm leaving!" Zipping the hat of the protective suit, Lu Wei put his hand on the steering wheel, increased the power output of the expedition vehicle, and then controlled the two expedition vehicles in front and behind to act together, boom, boom, three expedition vehicles, driving towards the outside of the base together.

Driving all the way through the long metal passage and crossing the gate of the base, which is nearly one meter thick, Lu Wei came to the outside of the base.

Desolation, endless desolation.

The sky is gray, the earth is yellow, the wind is whistling in the ears, and the billowing sand is like fog and rain beating on the windshield and metal shell of the expedition vehicle.

In the cockpit, the temperature began to drop, a little chilly, Lu Wei glanced at the thermometer, outside the car: -57 °C, inside the car: -23 °C, fortunately, he put on a low-temperature protective suit, otherwise, with a few single clothes worn inside, in this environment, he must be frozen half to death.

Environmental factors are not what Lu Wei is most worried about, he is more worried about the monsters outside the base, after the expedition car drove out of the gate, he saw all the way, many monsters gathered at the gate of the base, in the valley, in the dunes and caves, big monsters and small monsters, all over the mountains, hearing the movement, they all looked at several expedition vehicles with curious eyes, wandering and looking.

Fortunately, the monsters outside the base mainly use "free energy" as their basic survival needs, and occasionally fight with each other, one to devour special metals, and the other to absorb the energy on each other's bodies...... For objects that do not emit large energy fluctuations, they generally do not actively attack.

The energy system used by the expedition vehicle,The conversion efficiency is very high,The energy fluctuation generated is very small,There is not much attraction to the monsters,And the expedition vehicle is huge,More terrifying than the world master,That monster dares to take the initiative to come up to find fault,On the contrary,After killing a few monsters in the way,Other monsters are afraid to avoid it,They have retreated。

Lu Wei breathed a sigh of relief.

So, the three expedition vehicles drove north, running more than 10 kilometers in an hour, until outside the mouth of the valley, at a higher place, Lu Wei saw this boundless sea of sand in the north.

"This sea of sand is like the great Amazon plain, boundless, and it would be great if you put the base car here."

Lu Wei thought in his heart, and immediately controlled the acceleration of the expedition vehicle that was at the beginning, and he followed behind and drove into this endless desert sea.

The desert sea has no deep ravines and mountains, it is as flat as a mirror, and the expedition vehicles drive fast on it, like wild horses galloping.

However, after only half an hour, more than 20 kilometers, when the three expedition vehicles were marching all the way, a sand pit suddenly appeared on the originally solid ground, and the expedition vehicle in front suddenly fell headlong and sank rapidly.

Lu Wei was taken aback, and quickly stopped the two cars behind him, and tried to control it and get out of the expedition car that fell into the sand pit.

Through radio remote control, Lu Wei increased the operating power of the expedition vehicle trapped in the sand pit, causing it to climb out of the sand pit.

But sand has a property, very similar to a swamp, called density sedimentation, and sand is a fluid, the more you try to climb out with the help of the force, the faster and deeper it sinks, and finally it cannot be saved.

After struggling for five minutes, the expedition vehicle, which was no longer visible, did not move.

According to the terrain detector, the expedition vehicle that started is now located more than 50 meters underground.

Lu Wei's scalp exploded, he didn't want to think about it, he went the same way, and immediately went home.

After walking out of the sea of sand, Lu Wei still had some palpitations, "That sea of sand looks very flat, but there are a lot of quicksand and traps in it, and you can't get out if you go in, it's too dangerous to go north." ”

The plan to go north was ruled out, and after returning to the tower defense base, Lu Wei added an expedition vehicle, and Lu Wei headed east.

The terrain to the east is mainly rolling sand dunes, some of which are hundreds of meters high, very steep and daunting, and some of which are low and gentle, like walking on flat ground, and in general, they are also deserts.

However, the sand dunes in the east and the sand sea in the north are still a little different, according to Kai's guess, the sand sea in the north should be formed by countless years of weathering, thousands of meters underground are sand, the sand dunes in the east, the surface is sand, but the underground part is mostly hard rock, so walking to the east, there should be fewer quicksand and traps.

So, as Kai expected, Lu Wei drove three expedition vehicles and traveled more than 100 kilometers eastward in one day, and there was basically no danger.

The eastward route is confirmed to be feasible, but it is not particularly easy to walk, especially the tall sand dunes, which must often be detoured, and the field of vision is not wide enough, every time he encounters some tall sand dunes, Lu Wei has to release the drone to conduct high-altitude reconnaissance to see if the road ahead is good or not, which invisibly wastes a lot of time.

Therefore, Lu Wei also took a trip to the southern route.

The terrain in the south is more complicated, with a sea of sand, sand dunes, rocky mountains, and large mountain ranges, some places are easy to walk, some places are not easy to walk, and there are also many traps, such as when passing through a steep mountain range, the ridge suddenly breaks, and an expedition vehicle falls directly into the cliff.

Also, in the process of going south, in a relatively calm sea of sand, there was also quicksand, and another expedition vehicle fell in, because it was not deep, and finally climbed out, but when it came out, the bottom of the car was upside down, and it was impossible to drive back to the base.

Lu Wei lost two pathfinders in succession, and Lu Wei had to give up the southward route.

After weighing and comparing, then, the safer route that can be taken for the time being can only be the eastern route.