Start with an Exclusive Dungeon

Abnormal logins, closed persons, and system vulnerabilities are unexpected products of rules and isolated abnormal factors. A small chance to become in the world to come. . . It develops silently before the end of the world. Or weave a web of survival before the collapse of civilization and save the building from collapse. This is a lonely pioneer journey - enjoying the dungeon alone, but bearing the burden of the survival of hundreds of millions of creatures.