In the Chronicles of Darkness, the United States Federal Government gives tacit acknowledgement to the supernatural with the classification of a killer as a "Slasher".
According to the Federal Bureau of Investigation, a serial killer is a person who kills three or more people, commonly identified by a common modus operandi. Often, serial killers give themselves a "cool down" between murders, often for psychological satisfaction. Ted Bundy is a famous example of a "typical" serial killer.
Spree killers kill over a larger area than a serial killer, going through two separate stages in their murders. Guided kills occur when the killer is starting out, in a "comfort zone" where they can plan their killings. Mostly, the killer deviates, moving outside their comfort zone into the "random" phase, killing quickly and often indiscriminately. Often, there is no real cooldown period between murders, and often, a spree killers skip straight to the random phase, similar to Charles Whitman.
Mass Murderers take many lives over an even shorter period of time, sometimes only over the course of a few hours, often as part of a single event. Mass murderers do not have the time to create an M.O., instead they often commit suicide after their spree is finished.
Slashers are unique to the World of Darkness. The US Bureau of Justice Statistics defines a slasher killing as "killings involving at least three victims where the killer has capabilities that exceed the normal human spectrum." According to Federal law, VASCU must be called to the scene once a series of killings are determined to be caused by a slasher. This means that, according to Federal law, all supernatural killers fall under VASCU's jurisdiction.
Each Slasher is unique in his own bizarre way. They are compelled to kill and can be classified according to various Undertakings. Some have supernatural abilities, while others are, except for their urge, normal humans. All of them are terrifying.