Delta Green is a setting supplement for Chaosium's Call of Cthulhu horror roleplaying game, written by Dennis Detwiller, John Scott Tynes, and Adam Scott Glancy. It was published by third-party content provider Pagan Publishing in 1997.
Overview[]
Delta Green is a contemporary setting for Call of Cthulhu, and involves players taking on the roles of agents of the shadowy government organisation from which it takes its name. The organisation is dedicated to combatting any paranormal threats which present themselves to humanity, and ensuring that the nature of these threats remains unknown to the general public.
The setting was developed from a single scenario printed in The Unspeakable Oath, a Pagan Publishing fanzine dedicated to Call of Cthulhu, titled "Convergence". Delta Green has since become one of the most popular Call of Cthulhu settings, and now boasts its own stand-alone game system (albeit one which is still compatible with other editions), a host of supplements spanning an in-universe time period of several decades, and dedicated fiction. These have all been published through the Pagan label.