There used to be a transportation formation that connected the western border to Dahuang Swamp—something that was left behind from the time of the Tianling Dynasty's ancestor. However, it was no longer working due to the destruction caused by the elements and people over the years.
The current transportation formation was specifically set up by Shangguan Yue so that the Black Guards could conveniently travel to and from Dahuang Swamp. However, not many people knew about this matter.
…
Shangguan Wan's eyes lit up when she saw the transportation formation. "This transportation formation looks rather new. Did you specifically set this up, Lieutenant Mu?"
Mu Qinghe froze for a second, but he soon assumed his usual facial expression and calmly answered, "It was left behind by the late Crown Princess."
The smile on Shangguan Wan's face crumbled slightly. "…So it was left behind by my sister… I didn't know that…"