A sudden, deafening crash echoed through the air.

Accompanying it was a violent tremor, as if the very earth were shaking with fury, and the powerful howling wind sent a chill down the spine.

In an instant, Serena's heart pounded wildly. Her body broke out in a cold sweat, and she instinctively crouched down, reaching for something to hold onto. But the several-ton heavy wooden stairs beneath her feet seemed as fragile as paper, and they suddenly collapsed beneath ...