What is it?

DELTA GREEN was once a setting for Call of Cthulhu, created by the Delta Green Partnership (Glancy, Detwiller, & Tynes). Now, it is a standalone RPG based in the Modern Era. It revolves around a clandestine U.S. based organisation called DELTA GREEN, tasked with eradicating (and sometimes studying) the eldritch horrors faced in Call of Cthulhu.

It answers the age-old question of how to bring together player characters in a fluid and immersive manner. DELTA GREEN agents work in secrecy, using other U.S. government agencies to fulfill their tasks and agendas. But there are others out there – with a similar end goal, yet trying to achieve them via different means. DELTA GREEN comes with a rich and storied history of schisms and political infighting, drawing upon the federal alphabet soup folklore, modern legends, and all kinds of conspiracies.

The Game System

The 2nd edition of DELTA GREEN is built on the Misery Engine, as derived from Mongoose Publishing’s Legend OGL. though including some unique modifications.

The Sanity system has been further elaborated, now including types of Sanity loss rather than a general form; which leads to ‘adaptions’ and various character debuffs.

Another unique addition is the Bonds system, comprising of friends and family of the Agents that serve as character development tools and a sanity-mitigation mechanic. Bonds can be interacted with in ‘Home’ scenes: in-between scenario vignettes that focus on the average lives of the Agent, providing a stark contrast to the horrors faced later on.

Finally, the combat is streamlined – and is much more deadly. ‘Lethality’ is a new mechanic on some weapons that could outright kill an opponent.

Where do I start?

The Need to Know source book is a great place to start – featuring a quick-start set of rules, a demo scenario (Last Things Last), and pre-generated player characters, playable with up to 6 players.

After running through this introductory scenario, I suggest you purchase the DELTA GREEN: Hardback Slipcase Set, which includes the Handler’s Guide and the Agent’s Handbook – where all are essential in fully comprehending the dark and grounded universe this game is set in. Included is another introductory scenario: Operation FULMINATE: The Sentinels of Twilight, that is considerably more complex than the aforementioned.

Finally, Control Group is a compilation of four scenarios for novice Handlers (Game Masters) that introduce wide aspects of the world into your games, visiting varied and strange locales. Past this, a number of other scenario compilations are available – and more is on the horizon.

Things to check out

  • Dennis Detwiller’s Patreon – A treasure trove of short stories, miniature scenarios, and updates on upcoming scenarios, campaigns and source books. He’s an avid contributor and founder of DELTA GREEN, and very receptive to feedback and discussions.
  • The Fairfield Project – A wikipedia of resources for DELTA GREEN – it has everything that a Handler could ever want.
  • Impossible Landscapes – If you are interested in the mythos of the King in Yellow – look no further than this recently released campaign written by Dennis Detwiller that would positively melt your mind!
  • The Unspeakable Oath – Whilst this isn’t a dedicated resource for DELTA GREEN, it was where this RPG was born. It’s a fanzine comprising of scenarios, concepts, and discussion articles on Cthulhu Mythos roleplaying games. Sometimes there are DELTA GREEN scenarios hidden within.

Listen to these podcasts!

Mayday Roleplay: A DELTA GREEN actual-play podcast that’s rich in character development, interesting historical settings, and a friendly cast of members. They also dabble in Ironsworn and DnD!
Arc Dream Presents: A podcast by the publishers of DELTA GREEN. There are intermittent episodes that range from discussions, interviews, actual-play recordings and more based around DELTA GREEN and other games.
Black Project Gaming: Get read in! This actual-play DELTA GREEN podcast acts as a great insight into how the Bonds system shines in DELTA GREEN. Their campaign consists of numerous published scenarios, all beautifully connected. They also have a DnD campaign to listen in on.
The Green Box: A discussion-based podcast that’s centered in all things DELTA GREEN. It’s one of the most useful GM resources I’ve ever seen for DELTA GREEN, discussing supporting elements of the game like scenarios, house-rules, the Bonds system, and so on.


Operation FULMINATE: Sentinels of Twilight A Modern Era scenario set in the wilderness of the Yosemite National Park. Best suited as an introductory scenario for beginning players.

[PLANNING] Music from a Darkened Room – A Modern Era scenario set in a small New Jersey town. Beautifully haunting, best suited as part of a campaign for mature players.


More to come.


More to come.

Header image by Dennis Detwiller, titled “A SONG BEFORE TRAVEL”.

Published by arrangement with the Delta Green Partnership. The intellectual property known as Delta Green is a trademark and copyright owned by the Delta Green Partnership, who has licensed its use here. The contents of this web page and relevant resources are © The Membrane’s Journal, excepting those elements that are components of the Delta Green intellectual property. I am expressly prohibited from charging you to use or access this content. This web page and relevant resources are not published, endorsed, or specifically approved by the Delta Green Partnership.

© 2021 The Membrane’s Journal.