In the cave.
A white horse ran crazily on the ground. Before the gravel stirred up by the rampaging horse could fall, the white horse had already run dozens of feet away.
Shen Rulin lowered his body on the horseback and looked past Qing Xue's smooth mane into the darkness in front of him. Apart from anxiety, there was also a hint of vigilance on his face.
Although Qing Xue's speed was not as fast as him riding the Thunderball Sword, she was still fast. She had been running for nearly fifteen minutes, but there was still no sign of the passage coming to an end.
It still confused Shen Rulin how one could dig such a long underground passage.
As he was thinking, Qing Xue ran for another few thousand feet. Shen Rulin was about to speed up the horse when something flashed by from the corner of his eyes.