All ghost gods, whether from the Netherworld Race or the sea of red spider lilies, must personally visit the Mountain and Sea Realm.
This is not a clear regulation, but rather an unwritten rule of the Netherworld.
This unwritten rule originally came from the Netherworld Race's tradition of reincarnating into the Mountain and Sea Realm at intervals.
In fact, this tradition initially was just to address the personality disintegration issue of the Netherworld Race due to prolonged stay in the Netherworld.
Subsequently, at the suggestion of the Mother of All Stars, the Goddess of Death agreed to allow the Netherworld Race to vacation in the Mountain and Sea Realm periodically, to relax and regain their humanity.
As more and more ghost gods appeared in the Netherworld, this tradition from the Netherworld Race naturally became an unwritten rule for the ghost gods.
After all, ghost gods are ultimately not True Gods.
