First, it is a question of the practice method.

Liu Fang was in the library, searching for various kinds of martial arts that he might be able to use, screening, summarizing, and comparing them.

This process saved Chu Yao a lot of time.

Second, it’s a matter of money.

Without money, everything is over.

Not to mention that he has not yet paid the compensation to the Military God Academy, whether it is his own cultivation or the maintenance of troops in the future, it will cost a huge amount of money.

Now we have to find a way to open up a source of income.

After much thought, and with the help of Lu Hongzhuang from afar, Chu Yao finally found a more feasible way.

Selling invisibility agents.

Invisibility agent is a kind of "commodity" with strong monetization ability.

First of all, this product is currently only available to be refined by Lu Hongzhuang, and it can be produced in batches with a stable source of raw materials.

Secondly, the special ability of invisibility has great practical value, otherwise the Night Demons would not be so rampant.

Third, the invisibility agent is not within the scope of military-regulated sales. In other words, the military has not yet enacted laws to regulate its sale, and the current window of opportunity is perfect.

On Lu Hongzhuang's side...

At present, nearly two hundred doses of invisibility essence have been mastered.

In the expedition camp, all members above the Void Realm have been equipped with invisibility agents, and a total of about twenty doses have been consumed.

There are still many left.

However, in order to make reserves for other team members and to prepare for the creation of the "Invisible Team" later, Chu Yao did not sell many.

What's more, things are valuable because they are rare. If too much of this thing is released at one time, it will become worthless.

So now, only twenty copies are available.

Chu Yao found Hou Guanjun's channel and Duobao Mall's channel respectively, gave them each a copy, and threw it out to test the waters first.

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