Heavenly Stone:

Allows one to travel the Heavenly Realm, has other unknown uses. Allows user to bend his personal timelines.

He dreamed that the rock in his mind was called the Heavenly Stone and the space he entered was called the Heavenly Realm. Inside the Heavenly Realm, there were countless parallel worlds and universes alongside reality. When he returned to the current present time, an opening was left for him in the Heavenly Realm. Beyond that opening was the world that he had experienced in the Divine Sword Sect.