The apocalyptic crisis was a catastrophe that affected countless beings, even the Heavenly Dao Saints could be drawn into it. Minor impacts could lead to a regression in cultivation, while major ones could result in death and the obliteration of one's Dao, essentially wasting a lifetime of cultivation like water flowing away. It could be considered the grandest calamity within heaven and earth, but it could also be seen as the greatest opportunity.
During the apocalyptic crisis, the spiritual energy of nature of the entire Three Realms would experience massive fluctuations, thereby affecting the stability of the space of the Three Realms itself. The space of the Three Realms, as reestablished by the Hong Jun Daoist Ancestor, was not meant to withstand the full force assault of a Heavenly Dao Saint. However, during the ongoing apocalyptic crisis, the stability of space would be greatly strengthened, capable of withstanding the full onslaught of a Heavenly Dao Saint.