Serial killers are both some of the scariest and most interesting stories in the world. Maybe you've read about a few yourself, or maybe your partner watches Forensic Files on repeat (check your dinner for poison). Serial killers make good TV, that's just a fact. Hannibal Lecter and Buffalo Bill from Silence of the Lambs, Marco Amoretti from the chilling 'jungle cruise' episode of Ghost in the Shell: Stand-Alone Complex, and of course Norman Bates in the classic Hitchcock thriller Psycho. Anything about Ted Bundy, Jeffrey Dahmer, Ed Gein, or any number of other real serial killers will get eyes on it pretty easily.
Games are no different - you'll find a lot of serial killers in your favourites. Not the least of which being you, of course. Sure, you may be the 'hero' and all that, but let's face it... a lot of what you do in games is very serial killer-esque.
Murder three or more people, usually in the service of abnormal psychological gratification, taking place over a period of time longer than a month, often with time in between. But enough about you, let's talk about some serial killers in games - who aren't the player.
10. Vincent, The Whytechurch Murderer - Arcanum
Arcanum: Of Steamworks & Magick Obscura is a 2001 isometric open-world RPG with one hell of a long title. In Arcanum you play as the lone survivor of a zeppelin crash in a realm toeing the rift between magic and steampunk technology being the dominant force in the world.
Within Arcanum you can be tasked with investigating a series of deaths in the city of Caladon. The killer is an elven wizard named Vincent who is secretly possessed by a demon, L’anamelach. In order to successfully complete the quest you must research demonology, acquire an ancient dagger, and then kill Vincent with said dagger before he can transform into L’anamelach and flee - causing you to fail the quest.
Vincent, under L’anamelach's influence, manages to kill two people before you arrive on the scene and then he kills a third while you're in the process of investigating him. Similar MO in each of the first two cases - he used demon strength to force open trap doors and then climbed into their homes to get his murdering done.