Time flies, seven days later.

Tower defense base, main control hall.

Inside the crystal screen, Kai excitedly told Lu Wei that the reserves of the resource library were enough to start the upgrade process, and this base could be upgraded to a second-level base!

Lu Wei's spirit was shocked and he clicked on the resource center.

――

【Resource Center】

Energy Core: 1081

Normal resources: 772620

Special Resources: 152507

Towers: 48/48

――

High school chemistry says that molecules are in constant motion, and even if they are buried in mineral resources at a depth of 10,000 meters, their mineral molecules will move all the time...... This movement is called "Brownian motion".

The function of the resource collector is to speed up this Brownian motion, selectively absorb important mineral molecules, gather them on a device similar to a "suction cup", and collect them.

After the upgrade of the resource collector, the absorption rate of underground resources has increased by more than five times, and the production of ordinary resources alone has increased from an average of 4,000 units per day to 20,000 units.

Although the content of special resources in the soil is small, the amount collected by resource collectors is also about 2,000 units per day.

In addition, in the process of monsters invading the base, a considerable part of the body, shell, and bones left after death can also be converted into the resources of the base, especially special resources, which can convert nearly 3,000 units per day.

The steady increase in resource reserves has made Kai's expectation that the base can be upgraded after three months, but now it is nearly a month ahead of schedule, one reason is that Lu Wei's excellent work has accelerated the process, and another reason is that during the upgrade process, the base can be transformed and replenished at the same time.

The best time to start the upgrade process is when the resource reserve reaches about 70%.

"Wei, do you want to start the base upgrade process?"

"Start!"

"Yes!"

Buzz~

The underground turbines speed up and increase the power generation capacity, and with the ample supply of electricity, many corners of the base are as bright as day.

Boom boom boom~

The floor shook slightly, gradually getting louder, and in many places it became more noisy, as if you were in a huge factory.

Outside the base.

The monsters inside and outside the valley found that a loud noise was generated from the ground, humming and humming, and the ground under their feet was trembling more and more violently, so that there was an illusion that the earth was shaking the mountains.

Click~

Suddenly, at the edge of the base's buildings, pieces of metal flooring suddenly extended from the gaps in the edges, like drawers opening open to cover the surrounding dirt and rocks.

The base is expanding outward.

Da Da Da ~

Dozens of meters underground, a large drilling machine is excavating, large rocks into powder debris, through a large blowing and suction device, the crushed soil through a thick metal pipe, blown to the outside of the base, in the original chaotic and dim space, set off yellow dust.

Space expansion is only the first step, in the next few days, a large number of materials, mechanical devices, instruments and equipment needed in the process of upgrading the base will be continuously developed and produced from the scientific research center...... The entire site has been turned into a busy construction site.

"Whew~"

The monsters outside the base were restless, like ants on a hot pot, walking around the base anxiously, letting out all kinds of howls.

……

After the base upgrade process is activated, a large amount of electricity will be consumed during the upgrade, and the turbine power will increase, and the production of energy cores will be reduced by about half, and the production will be restored soon after the upgrade is completed.

In addition, so far, the base has launched four Plane Shuttles, and the number of energy cores in the current resource pool is 1081, and if nothing else, the fifth Plane Shuttle can be launched tomorrow.

However, the base is in a state of upgrade, and Kai suggests that the plane shuttle be launched after a while to be on the safe side.

Lu Wei nodded, but he didn't expect that the plane shuttle had already been launched to the fifth ship.

A wave of less than 2,000 monsters entered the base and were all wiped out.

Lu Wei made his bed and prepared to start cultivating.

The base is being upgraded, Lu Wei can't go to the energy center to lay on the floor, the noise there is as loud as thunder, he can only stay in the main control hall that is not particularly noisy to cultivate-although the concentration of free energy here is not very high, but it has little impact on Lu Wei's cultivation, in this environment, he also absorbs the free energy in the air.

Cross-legged on top of the bed.

Inhale, exhale.

Countless tiny amounts of free energy gathered in Lu Wei's lungs.

Through the gas exchange of the capillaries of the lungs, the free energy enters the dantian.

Dantian, where the human body's spirit and spirit gather, is divided into upper dantian, middle dantian, and lower dantian, which are located between the forehead and eyebrows in the midline of the human body, the middle of the ribs in the chest and the navel eye of the abdomen, just above the three golden section points of the human body.

Through the internal circulation of the human body, any gas (such as air) can enter the three dantians, such as the upper dantian located on the forehead of the human body.

The middle dantian, located in the middle of the two breasts in the chest, is very close to the lungs, and it is a very suitable place for gas exchange, and there is no problem in storing free energy.

Xia Dantian, that is, Zheng Dantian, also known as "Qi Sea" and "Mud Pill Palace", is located near the kidneys of the human body, is "the place of essence", "the place of hidden life", is very important to the whole body of the person, far more important than the middle dantian and the upper dantian, Xiuzhen or martial arts novels said dantian, generally refers to the lower dantian.

Lu Wei uses the abdominal breathing method to cultivate, and can only store a small amount of free energy near the middle dantian very close to the lungs, but because the free energy is an extremely small particle, like volatile alcohol, it is not easy to preserve, so far, Lu Wei's body has only stored a very small amount.

The storage problem was solved, but in the process of calling, Lu Wei still encountered some practical problems.

In the dantian, the free energy is static and does not flow, how to call it?

At this time, Lu Wei understood why the words "meridians" and "Zhou Tian" were emphasized many times in many novels, why? It's like an engine, even if there is oil in it, but if you don't start it, how can it run?

Only by letting the free energy in the body change from static to dynamic, circulate and spread to all parts of the body such as hands, feet, brain, waist, internal organs, etc., can it exert great power.

But there are two problems that need to be solved.

One is the strength and toughness of the body, "if you want to cultivate the truth, you must first practice the body", without a strong body and meridians, how can you withstand the rapid flow, oppression and impact of the free energy itself?

The second is spiritual power, just like the heart in the human body that makes blood flow, free energy flows and circulates in the meridians, and it also needs a power drive, what is this power? There is no doubt that it was in the process of cultivating in these days that Lu Wei discovered the "spiritual power".

Psychic power, ethereal, but it does exist, according to Kai, it is "power from the soul".

Both problems are not easy to solve.

A strong body refers to "physical skills" and "hard skills", honing the muscles and bones, and it is best to let the body reach the point of invulnerability.

Lu Wei has no clue about the cultivation of spiritual power, according to the setting of some novels, I am afraid that it can only be achieved by taking some genius earth treasures and comprehending the laws of heaven and earth, instant epiphany, breaking through the entrance of life and death, and so on.

The two questions made Lu Wei understand that cultivation was not what he imagined, as long as he sat on the ground and waited for a period of time, he could become a peerless master, it was far from so simple.

However, he was full of confidence, because, at least he had found that way, and moving forward, coupled with the convenience brought by the tower defense base, and the free energy that no one could access except him, he would definitely be unstoppable on the way of cultivation.