Audiobook Ice Cold Killers - Addicted to Death by World History. What makes a serial killer? There is a huge difference between killers who kill once in the heat of the moment, mass murderers who slaughter many people at once, and serial killers who follow a specific pattern to kill carefully selected victims. A serial killer is an ice-cold predator who enjoys the hunt, is driven by ritual or a particular impulse, and who becomes increasingly dependent on the release that the murder provides.