I disagree on the crime of opportunity. There are far easier target for someone to kill if this wasn't personal. Attacking a house full of people isn't exactly the smartest idea, even if it worked out for him. The attack, albeit obviously planned, seem chaotic to me and not well organized. Take for example someone like ONS - he always came prepared and never took any chances. He knew exactly what to do and how to do it even if he was extremely bold. This killer, in contrast, seems very amateurish to me.
For one, as I said, multiple people in the same house isn't good not only for your own safety, but because they can easily alert others. Then you have also the fact that the killer was also armed with a simple knife. Also not the greatest idea. The house as a location is also a very bad location - not many routes to escape from, house is three stories, the area is very active and filled with people due to close proximity to student apartments and the fraternity buildings, etc. Obviously everything seems to have worked out for the killer so far, but there is a literal myriad of things that could have gone wrong during or after the attack
This is why I think this is personal. The amount of risk he took is insane when you think about it. Either personal or the killer is a complete imbecile who somehow lucked out.
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