A Twin World: The story takes place in a universe where the outer world, the "Bright Realm," and the inner world, the "Nether Ruins," seep into each other. The two worlds coexist like mirror images, and every thousand years the "World-Erosion" phenomenon blurs the boundary between them.
Spiritual Energy System: Cultivators gain power by absorbing "spiritual essence," progressing through nine realms. The strongest, those in the "Heavenly Gate Realm," can briefly cross the barrier between worlds, but at a tremendous cost.
Ancient Calamity: In ancient times, a cataclysm known as the "Age of Eternal Night" caused the two worlds to collide. It gave birth to a terrifying entity capable of devouring worlds, known as the "World-Eater," which seven sages sealed away at the cost of their lives.
