DaoistFvlVBt

IMO, it makes more sense for someone like MC to become even more evil as time passes. Slowly losing his attachment to his past home as he commits more and more "unscrupulous or immoral" acts. Detached from everything and everyone but his pursuit of strength. People don't suddenly go from "a symbol of massacre and death" to a good person. It tends to be the other way, the more evil you do the more evil you become.

Don't be so naive author. Most people reading your novel like the MC the way he is now, and the way he was described in the synopsis. That's why they are reading it in the first place. Anyone who is willing to read a bunch of chapters of a novel with an evil MC isn't going to be happy if he suddenly has a change of heart and becomes good. I would recommend to stay loyal to the synopsis, let MC become the "powerful demon god" that "will kill anyone who stands in his way or possesses something he needs". Unless you want to piss off most of your readers just to satisfy one guy's wishes.