Just started it! Well timed.

Personally I think straight-up Slasher movies should be excluded from this challenge, unless there is some focus on the police investigation, or it is explored in some detail why the killer is commiting these crimes and their motivations.. otherwise where do you draw the line between something like Friday the 13th and Henry: Portrait of a Serial Killer.

Fair enough! Personally, no I don't think the Friday the 13th movies should count because if you consider at least the first movie, the motivation of the "killer" is vague and not revealed until the "twist" ending. It's a straight up slasher. However, I think something like Halloween could count because at least there is a police presence, a "chase" to stop the killer, and some motivation behind the killings - the background of Michael's mental state is briefly explored, which in turn justifies why he commits the crimes. You don't get any of that with Friday the 13th really.