The progression of Five Qi Chaoyuan into Innate Qi granted Wang Sheng the qualification to create worlds.
However, the system of reincarnation is only in its nascent stage.
According to his memories of the Underworld, many things are still lacking in this world.
"The most crucial is the Six Paths of Reincarnation; every soul will enter the Six Paths of Reincarnation to be reborn... it is the core and also the most mysterious aspect of the Underworld, something that cannot be omitted. However, for me right now, simple rebirth is possible, but I'm still far from achieving the Six Paths of Reincarnation."
The Six Paths of Reincarnation seems merely to send the souls of living beings to various worlds for rebirth, with no particular difficulty.