Behind the Tianyun Blood Night a hundred years ago, there had always been a hidden thread no one knew about, and the key to that thread was this mysterious black energy.

Ye Feng carefully stuck his head out of the hole. Inside, it was pitch-dark. But when he condensed a strand of golden Profound Qi, the sight before him made him suck in a cold breath.

What kind of monster was that?

Outside the opening lay a spherical underground chamber, several hundred meters across, vast and spacious. In the middle of that enormous spherical space floated a small, semi-transparent black sphere, only a few meters in size. The dense black energy Ye Feng had sensed was radiating from the sphere's surface.