Those who could enter the Fiendish Corpse Secret Realm twice were the Core Disciples of the five major sects.
They were Yin Corpse Sect's Mo Jingyuan, Hehuan Sect's Feng Ling'er, Ten Thousand Ghouls Sect's Gui Ming, Soul Devourer Sect's Qian Hun, and Black Fiend Sect's Li Kun.
Each of these five people recounted their own experiences. In the end, they came up only with a few points of difference.
Firstly, changes in the environment. Land, clouds, smell, and so on were different from before.
Secondly, the order had changed with the Fiendish Rain falling before the Fiendish Corpses appeared.
Thirdly, the Fiendish Corpses themselves had changed. Now they had the strength of the Iron Corpses although they possessed only ordinary Fiendish Pearls.
There were lots of speculations from everyone about the reasons for these changes.