The sound was not thunder.
Thunder was organic, uneven. Then he punctuated by sharp sky cracks that decayed through natural sound scattering. The sound rolling over the northern mountain ridges was nonstop, rhythmic, and clockwork. A hollow, droning roar that shook at exactly twenty-four cycles per second, shaking the pine needles from the mountain trees and sending ripples across the surface of the roadside puddles.
Lin Tao and Tie Shan crested the ridge overlooking the great northern mountain pass.
The pass was a natural granite bottleneck three miles wide. It was flanked by sheer cliffs of gray limestone. Ancient Precursor boundary pylons—slender obelisks of polished black dark rock etched with dormant circuitry—stood like guards along both ridges, marking the legal frontier between the Seven Southern Provinces and the central territories of the Celestial Empire.
Through the heavy morning clouds that choked the pass, twelve massive shadows emerged.
They moved not with the graceful flight of birds, but with the terrifying, unnatural floating lift of floating fortresses. Each warship was three hundred paces from stem to stern, its hull built of iron-banded sky cedar and clad in thick plates of cast bronze dragon-scale armor. Along their lower keels, massive circular floating arrays—each thirty paces across—pulsed with angry, blinding violet light, vomiting plumes of white-hot steam and spark-charged ozone into the clean mountain air.
