Ling Han and his group did not waste any time. They entered into the Two Realm Battlefield, and headed in the direction of the Netherworld.
Ling Han was not the only one. Both Empress Luan Xing and the Heavenly Phoenix Divine Maiden aimed to enter into the Celestial Realm, so they naturally could not simply aim for becoming Saints. Thus, the two women also had to enter into the Netherworld to experience the different Regulations of the heaven and earth.
They were the advance party. In the future, the Rain Emperor, Ding Ping, and the others would also enter into the Netherworld. Of course, if Ling Han's rate of cultivation was fast enough, he would be able to draw them all into the Black Tower and take them with him into the Celestial Realm.
The Regulations of the Celestial Realm were complete, so there was no need for them to comprehend on both ends.