I'm pretty sure that Xu Luochen is the demigod. It was introduced right after talking about his past.
After all, but the time Ye Ping ascends all of his sect brothers and sisters have to be as awesome as he thinks they are to keep up the deception.
Who are bailian and changming? Also it's gotta be the MC. So he's a demigod eh? I wonder how someone got a hold of a soul from another world to inject into the egg.