In 20** AD, an accident changed the established direction of the earth's civilization!

It is now the year 21** A.D., about a hundred years ago, mankind initially achieved world peace, thinking that there would be no more wars again! In order to enter the cosmic age and fly out of the solar system, countries have stepped up efforts to develop various high-performance spacecraft.

But in the end, it was discovered that no matter how fast the spaceship was, it was too slow for the infinite universe, and it was impossible to get out of the solar system with spacecraft technology. So he changed his thinking and developed wormhole technology.

In an experiment that gathered the world's top scientists and gathered the world's energy to open the wormhole, a breakthrough was finally achieved. However, the experiment caused irreversible damage to Earth's space, and it was only then that it became clear that wormholes could not be opened in near-Earth space.

The instability of Earth's space has caused a global geological catastrophe that has lasted for 30 years. By the time the catastrophe is over, the global population has been reduced by more than 60 percent. Science and technology, on the other hand, have regressed greatly, and have only recently gradually recovered.

After the space was stabilized, an unknown number of spatial caves were discovered, and the doors to each unknown space were opened at regular intervals. These unknown spaces are known as "secret places".

There are also humans, humanoids, and various beasts and monsters in these secret realms, and even mythical beasts such as dragons and unicorns.

These secret realms are large and small, and the big secret realms are opened once a year, and each time they are opened, dozens or even hundreds of people can enter. The small secret realm is opened once every few years from time to time, and only a few people can enter at a time, or even only one person can enter.

At first, people didn't pay much attention to these secret realms, because neither humans nor beasts in the secret realms could enter the earth space through the space caves. And it's strange that earthlings who are more than thirty years old can't enter the secret realm through the space cave. But there are always adventurous young people in the world who are willing to explore secret places.

When these original explorers returned, things changed. There are forces in these secret realms that the earth does not have! Maybe it's no longer there's power! For example, cultivating immortals in the secret realm of Shenzhou in the Huaxia region practiced swords, seeking immortality. In the secret realm, it is easier for even ordinary martial artists to break through their limits!

And the Nordic secret realm, located at the junction of Russia and the Nordic countries, contains a secret method for exercising the body, which can finally make the body indestructible, ignite the divine fire, and the body becomes a god!

The secret realm of Olympus in Greece is similar to that of Northern Europe, but it is about seizing the bloodline, changing the bloodline, and finally realizing or seizing the godhead to become a god! Although there are no rumors of anyone becoming a god in Britain's magical realm, there are also legendary wizards whose lives are extremely long, or the life box of the Dark Lich King is immortal!

These are like ancient myths, and legends of immortality. So that people flock to the vultures and rush to go.

When the news of the secret realm came out, the entire earth was boiling, and everyone was crazy about immortality or invincible power! The governments moved quickly to keep the entrances to the Secret Realm and the explorers who entered it.

This displeased the free-spirited explorers, who began to revolt. After fighting for a while, governments suddenly discovered that although the first adventurers had not been in the secret realm for a long time, their strength was not very strong. But there are many ways and tricks of their strength, and modern personal weapons have not done much for them, and the damage caused by weapons of mass destruction is too great.

In desperation, governments around the world changed their tactics, co-opted and divided the adventurers, and used high-ranking officials or righteousness to win over some adventurers. Only then did he gradually gain the upper hand and control the entrances of the various secret realms in his hands.

Although I don't know why the secret realm was formed, with the in-depth study of the secret realm in various countries, countries have gradually understood the laws of the secret realm.

It has been found that the number of humans who enter for the first time after the entrance to the secret realm is always fixed every year, but the re-entry of adventurers who have entered before does not cost the quota.

And the adventurer who enters the secret realm, if he can't break through the innate realm (beyond the mundane) or the similar realm of other secret realms before the age of thirty, he must come out of the secret realm before the age of thirty, otherwise he will fall into the heavenly punishment and die! After that, there are restrictions on all age levels.

It seems that the secret realm has its own mind, forcing the adventurers who enter to desperately improve their strength, and if they can't reach it, they will be eliminated, and thus kicked out of the secret realm.

And the earth space does not know whether it is the lack of aura or other substances, and the adventurers of the innate realm and above cannot improve the realm strength after they come out of the secret realm.

With so many restrictions, people's desire for immortality has finally cooled. But governments around the world have found that well-cultivated adventurers are simply national strategic weapons! Especially among so many adventurers, there will always be a few people who are amazing and can cultivate to a very high and profound realm, and these people are called "strong people in the town"!

After discovering the power of cultivators' representatives, governments all vigorously selected young people with cultivation qualifications in their countries to participate in the activities of exploring the secret realm.

And the secret realm is not a safe place, every year the teenagers who enter the secret realm will die a large number of people due to various accidents, and even more than 50% of the explorers who die in accidents every year!

Even that can't stop people's enthusiasm for exploring secret places! Countless people have done their best to become an explorer!