It is said that the treasure is related to the legendary True Spirit of Kun Peng.
To enter, one must possess the blood of Kun Peng.
However, only the Imperial Clan of the Sea Race has the blood of Kun Peng. Moreover, it must be from the top echelon of the Imperial Clan; otherwise, the purity of the bloodline is insufficient for entrance.
Lu Jingkong used to enter the secret territory multiple times in search of a method to access the treasure.
She eventually found the method.
It was the martial method she chanced upon - the Twelve Startle Cicada Skill.
As long as she mastered this martial method, she could merge the True Blood of Kun Peng and transform into the form of Kun Peng, allowing her to easily enter the secret territory when the time came.
Unfortunately, while she had fully mastered this martial method, she lacked the True Blood of Kun Peng for the merger.