Shen Yangge studied the historical records covering the walls. They documented the exclusive authority over the "Imperial Secret Guards" granted by Great Chu's founding emperor.
Judging by the carved grooves, many years had passed, yet the writing remained clearly legible. Evidently, even if this secret passage saw little use, someone came to "clean" it at regular intervals, preserving the inscriptions to this day.
Great Chu's founding emperor was named Chu Luantian. To restrain the powerful ministers and various factions that had helped establish his dynasty, he created a counterweight comparable to the "Embroidered Uniform Guard" to prevent any one force from dominating. This divided authority among four factions within a single court, allowing them to keep one another in check.
At the time, the first emperor was highly wary of the independent authority vested in the "Imperial Secret Guards." He even arranged for four princes to be secretly observed after his death, to determine which of them had the greatest potential to inherit that authority.
Unfortunately, once the four princes discovered this enormous prize, they slaughtered one another, leaving not a single suitable successor to the independent authority over the "Imperial Secret Guards."
Later, the emperor could only choose one of his remaining younger sons. The second emperor was just twelve years old at the time. How could a child that age understand the importance of such authority?
As the dynasty's founder, the first emperor could not bear to see the realm he had painstakingly united fall into the hands of another family. He could only divide the independent authority over the "Imperial Secret Guards" into four portions, placing them in the hands of the Grand Tutor, the minister, the court historian, and the Ministry of Justice.
Only under the fourth emperor was the independent authority over the "Imperial Secret