Global Demonic Tide—my Category Is Unknown

The tide of magic energy swept across the world, demons were rampant, and humans retreated to the giant wall city. Magicians have become the pillars of civilization, but external demons are surrounding them, and internal resource struggles and class conflicts are becoming increasingly acute. Under this dangerous wall, young Lin Fan awakened to an unprecedented "unknown system" - it could not drive gorgeous elements, but could see "flaws" in the world's most basic structure and energy flow.