Talk:Neutral Route/@comment-186.78.95.230-20151014205437/@comment-122.57.173.238-20151018034230

I have tried that out before. If you go about killing all enemies in an area until "but nobody came" appears and all non-bosses, the game is mostly the same spare a few slight changes. One is that in Snowdin town has a slowed down version of their song, and people report of "feeling unsafe" and it being "unusually quiet". Undyne accuses you for killing just for the fun of it (though this might be similar in neutral routes? Apologies, I have not done the any neutral routes yet.) The call from Sans explains is the same for "Only Mettaton slain, Papyrus befriended."

From my run, those are the only difference I got. There are likely other things I missed or didn't get to experience because of befriending / not friending specific characters. Hopefully that will sate a little of your curiousity!