"How did this be done? The star system of the Samsung system, coupled with so many planets and space cities, can actually hide in front of us, and our detection equipment has not noticed it at all!" Chen Hong exclaimed in the communication channel.

"It's so amazing. What kind of technology is this?" Lu Xing was also puzzled.

"How could this happen? If the space city is invisible, it would be fine. How can such three large stars be invisible? How can they block their heat and light? And gravity since we entered the Butterfly Star Cluster, the gravity detection system has been disturbed and failed." The academicians of the Academy of Sciences thought and discussed.

"Green Pupa, our bodies need to communicate through subspace to have self-awareness. Is it okay to enter it?" Du Xingyu asked.

"No problem, the sub-space information is not isolated here." Green Pupa said, "Go in quickly, the time to open the channel is limited."

After receiving a positive answer, the human trade ship flew in from the passage. On the way, the ship kept recording data.

"There are hyperspace fluctuations here, and this channel looks like a wormhole!" Pei Jia said, "It's similar to the wormhole data we got from the Blue Star civilization."

"This should be a wormhole." Jiang Jun analyzed, "Is the free civilization trading market not in the Butterfly Star Cluster, but in the farther universe, where we go through the wormhole?"

Just a moment after entering the passage, the passage was closed and the commercial ship came to this market space.

"Why would you like to ask directly." Du Xingyu asked Green Pupa directly, and asked: "Hiss Green Pupa, did we just enter here through the wormhole? Is there still a butterfly star cluster here?"

"Of course!" When the Green Pupa talked to them, he looked like a human. He explained: "The one you just passed through was indeed a wormhole, but it was not a wormhole connecting two space-time, but a wormhole that opened a four-dimensional barrier."

"Because you are a third-level civilization and have not yet been exposed to space technology, I will explain a few more words."

"A four-dimensional barrier, simply put, is a barrier of four-dimensional space. The creatures in the three-dimensional world cannot see the scene in the four-dimensional world without special methods, so when you navigate in the universe, all your perceptions of the outside world are blocked by the four-dimensional barrier."

"Whether within the four-dimensional barrier, everything in the three-dimensional world can be clearly observed."

"The free civilization market is here, inside the Butterfly Star Cluster, you have not gone to the distant universe and space."

The explanation of the green pupa has opened the horizons of human commanders and scientists.

"There is such a thing!" Chen Hong said, "If our star system is wrapped in a four-dimensional barrier, wouldn't it be that the enemies of the same level 3 civilization will not be able to see us at all?"

"It should be more than that!" Du Xingyu said, "The four-dimensional barrier not only blocks the 'visit' of the three-dimensional world, but also blocks the matter in the three-dimensional world!"

"Commander Du's consciousness is that this barrier can withstand our weapon attacks?" asked Touls.

"That's right!" Du Xingyu nodded, "As you can see, most of our weapons are matter from the three-dimensional world, and they will be blocked before they come into contact with the four-dimensional barrier. From low latitude to high dimension, one energy level needs to be improved! From high latitude to low latitude, it can release energy itself, which means that the enemy can attack us wantonly!"

"It's so scary!" Turs realized the terribleness of this technology. "As long as the enemy has a four-dimensional barrier, it's easy to defeat a level three civilization!"

"More than that, the emergence of the four-dimensional barrier means that the fourth-level civilization has been exposed to the technology of dimensions and space. This is to crush the third-level civilization in all aspects!" Du Xingyu said, "Fortunately, the butterfly civilization is not our enemy, otherwise it would be easy for them to destroy us!"

"Dear guests, let me introduce the area in the free civilization trading market." Green Pupa continued to introduce, "We have three main markets, namely the secondary civilization trading market and the third-level civilization trading market, and there is also a star pirate civilization trading market."

"The second-level civilization trading market is mainly a place to trade for our butterfly civilization's affiliated civilizations. Guests can go to the third-level civilization trading market."

"Star Pirate Civilization Trading Market?" Chen Hong asked curiously, "Old Green Pupa, can Star Pirate Civilization be free to trade here?"

As the destroyer of the Milky Way civilization, the Star Pirate Civilization is hostile to many civilizations.

Green Pupa said: "Of course. The Star Pirate Civilization itself is just a wandering civilization, and they often need transactions more than ordinary civilizations. We are willing to provide them with this place."

When everyone thought about it, they felt it was reasonable.

Most of the predecessors of the Star Pirate Civilization were destroyed. At this time, they would sell resources, population, technology, and what they could sell, and even their own affiliated civilizations could be sold in exchange for opportunities to survive.

For Butterfly Civilization, instead of letting the Star Pirate Civilization Alliance set up its own trading location, it is better to include these transactions under the company and benefit yourself.

"I'll take you to familiarize yourself with the third-level civilization trading market first." Green Pupa said, "As for the Star Pirate Civilization Trading Market, you can visit it later."

"Okay." Du Xingyu agreed immediately, and their trade ship flew to one of the space cities.

This is a super city with a circular double-layer plane, with a surface area equivalent to the surface of twenty earths spread out!

This space city has another alias, called the Upside Down City. Because it has double-sideds, on one plane, the building extends upward and downward respectively, artificial gravity allows the gravity of both planes to point to the plane layer.

If you want to define an upper part of the Overturned City, it is the third-level civilized trading market; as for the lower part, it is the Star Pirate Civilized Trading Market.

In the upside-down city, most people take small spacecraft to trade, and human civilization is no exception.

Under the guidance of the green pupa, they entered the third-level civilized trading market, and the first stop was the "Star Coin" Bank.

"Welcome to the guests of human civilization to Xingcoin Bank." In Xingcoin Bank, the staff are real butterfly civilization tribesmen. They all look very dazzling. Even if they look at it from the aesthetic perspective of humans, they can still be called "beautiful as a flower".

However, the gender of these butterfly civilization tribes is different from that of humans. They are hermaphrodites. If a pair of butterfly civilization tribes fall in love, one of them will become a male and the other will become a female. Once they have given birth to offspring, they will return to their hermaphrodite gender status.

At this time, their marriage will be declared over and both parties will be single again. The next time they fall in love, the identities of male and female will be exchanged.

This is somewhat difficult to accept from the moral concept of human beings. But after entering the new era, human beings adhere to one principle and meddle in other people's business!

"At the Star Coin Bank, you can exchange the trading resources you carry with you into the corresponding Star Coin Points to purchase items in the trading market. You can keep these Star Coins or purchase the resources you need when you leave. Our butterfly civilization ensures the safety of Star Coins." Green Pupa said.

Star Coin is a currency provided by the Butterfly Civilization to facilitate trading and is only useful in this civilized trading market, so it is also called Butterfly Star Coin.

Basically all civilizations who come here will exchange star coins, because even if the transaction is not successful, they can return the star coins and take away their trading items.

If it really doesn't work, you can also buy some items sold by Butterfly Civilization directly. In this trading market, the biggest seller is actually Butterfly Civilization itself!

"Resources, population, technology, information, affiliated civilization, territory... everything can be used to exchange star coins." said the salesperson of Star Coin Bank.

"Then check out the information we brought!" Du Xingyu took out the list. These were the transaction items they brought on this trip.

Among them are some rare materials, antimatter, some scientific and technological information, etc.

The salesperson quickly finished counting and handed Du Xingyu a ball of light.

Yes, it is a ball of light! This is a kind of technology that binds a ball of photons together, and the photons record information. These photons are equivalent to supercomputers, and just a ball of light the size of a thumb can record all the information on the earth at present!

"After your resource evaluation, the total value is about 301.2 million star coins. These star coins have been stored in this ball of photons. If you want to exchange for more star coins, you can use the light ball to evaluate and exchange the star coins at any time." said the salesperson.

"I suggest that guests go to the trading hall first, there will definitely be something you are interested in." Green Pupa suggested.

"That's it." Du Xingyu walked, looking at the trading market manual to learn about various information here.

The place where the trading hall is located is a giant polygonal building.

As soon as you enter, everyone can see all kinds of creatures.

Carbon-based organisms have the most common ones, including humanoid organisms, Zerg-like organisms, marine organisms, and civilizations like giant beast civilizations and plant civilizations.

Here, Du Xingyu also saw the silicon-based civilization in the Milky Way for the first time. Their numbers are much smaller, usually appearing in robotic states. If it weren't for the logo hanging on them, Du Xingyu wouldn't have known that they were creatures of silicon-based civilizations.

In addition to them, I heard that there are some civilizations of special races here. They were born in a special environment in the universe and were even less numerous than silicon-based civilizations. Du Xingyu has not seen it yet.

"The information trading window, here is a complete intelligence system, scientific and technological information, resource information, everything you want to know!"

"Resource trading window, are you still having a headache about the scarcity of rare resources in civilization? We have fewer scarce resources. Today we recommend photonic materials for sale at 10% off!"

"The population trading window, we have populations of all races, whether scientists, artists, or companions, and pets, and we also accept genetic customization..."
Chapter completed!