I don’t think we know enough to say at the moment but we do know the weapon was a KaBar. Reading about this knife is quite terrifying, it’s used for hunting and by soldiers so not just a bog standard knife from a kitchen.Forgive the grim question (and I don't want to sound like I'm blaming Dylan because there's a whole host of reasons why it took so long to call 911) but how on earth can 4 people be stabbed to death without hearing screams? Would they have died instantly?
On Reddit there was a post about how sharp this knife is, how just pressing it to your hand could draw blood.