What Si Huai said was actually quite simple, but it was not so easy to understand.
If Si Ren could time-travel the first time, he could do it a second time. That meant the moment he was about to step into the transmission portal, the outcome was already sealed.
In other words, perhaps long before Si Ren decided to return to the past, his future self had already entered this point in time and made changes in the exact same way he was doing now. Or perhaps he had tried tens or thousands of ways he had never imagined, yet none of them yielded any results.
Chapter 907