Prison!

A tear opened in space on an ordinary mortal planet, revealing countless alien beasts beyond human understanding. They poured into the human world, bringing unprecedented disaster to the planet.

In the midst of the calamity, 23 mysterious powerhouses emerged. Calling themselves the Apocalypse, they founded the Apocalypse Organization and taught people how to cultivate. They then took up permanent guard at the rift in space, naming the area the Apocalypse Battlefield.

A thousand years passed, and the course of human civilization had changed completely. Countless people rushed to join the Apocalypse Organization, seeking strength and a chance to explore the Apocalypse Battlefield.

After accidentally revealing his abilities, a seventeen-year-old boy of unremarkable background was selected to join the organization. Despite having what the world considered the lowest-grade spiritual aptitude, he grew into a true powerhouse.

The spirited young man became invincible in his age. But as time went on, he discovered that the so-called Apocalypse Battlefield was actually a prison!

And humans and alien beasts alike were nothing more than prisoners inside it...