When the plane was first created, all three realms were mixed together. Only when the Heavenly Dao was created, and the nomological force was formed, did the division of three realms start. And what Lonemoon had to do now was to divide the three realms. So long as the three realms were completely separated, the problem of the human race that Hong Meng worried about would no longer exist. In addition to that, there were all of Lonemoon's earlier efforts which established Daoist teachings among the humans. Though they still couldn't fight the divine race, they were no longer completely defenseless.