In my opinion the killer "knew" the victims. Thats not to say any of the victims knew the killer, if you can follow my drift. The fact of the method of death says to me that it was personal. Again, not to say the victims were or were not acquainted with the perpetrator.I am by no means a criminologist but if the grudge was against ‘the house’ (either due to not being admitted to a party, or jealousy of young good-looking kids or whatever) with no specific target then arson would seem the obvious way to exact revenge. I’m thinking of the Childers Backpacker Hostel murders over in Aus but I am sure there are many other examples.
The method used here, leaving behind lots of messy evidence, needing lots of planning, and the risk of other occupants waking as you take out multiple people one-by-one, seems like something else. I’m not sure what but possibly only one intended victim and the rest were collateral damage?
As I say I am just an amateur but keen to hear other people’s thoughts.
The perp DEFINITELY knew them. I believe the killer spent at least 20 min in the house. Probably more. I also believe this was planned but not some months long stalking type of event. Definitely not spur of the moment tho.
I do not believe the killer has any injuries from his own weapon. I believe the killer had a ski mask type covering and gloves. I don't believe he left DNA behind after the act. (Mouth and hands and hair covered. Did not slip on the knife due to its design so not bleeding)
I think its possible that he wore a tyvek type painters suit also. I also think he had other weapons. All is just my opinion of course.