Quote Originally Posted by Chakramaster View Post
Actually there's something even deeper too. You get a set number value in your coding when you start playing. Depending on your value, you may get different things to happen. It'll determine certain things that may be hidden like some secret doors, hidden characters, or dialogues. So in a sense, each run could be different no matter what type of playthrough you're doing. Tends to only work in Pacifist though.
Wow, I never noticed this even on my second Pacifist playthrough. There were a few subtle differences, but I don't recall anything too significant, though.