@JohnAustin
Well, the word could have also been invented off the cuff by someone who was being chased by a guy holding a live chicken in each hand.
I'd say the human condition compels some gray level of narcissism in everyone, at least toward meeting basic needs. The energy required to commit a mass shooting is assuredly psychopathic, whether owing to bad wiring or ongoing personal despair and misery; usually some combination of both.