The Unspeakable Oath is an award-winning quarterly magazine dedicated to tabletop roleplaying games that are based on the Cthulhu Mythos -- the creations of horror author H.P. Lovecraft, the writers who inspired him, and the writers who followed him. Created and published by game designers, writers and artists who love Cthulhu Mythos gaming, every issue provides ideas, inspiration, tools and techniques to make your games more horrific than ever. The Unspeakable Oath 20 includes: This issue's foreword by editor-in-chief Shane Ivey. Reviews of games, books and movies that are of special interest to Cthulhu Mythos gamers. Reviewed in this issue: Musica Cthulhiana, Cthulhu's Dark Cults, Curse of the Yellow Sign Act 1, Machine Tractor Station Kharkov-37, Marble Hornets: The Complete First Season, The Watchers in the Sky, Cthulhu Invictus, Halloween Horror and Murder of Crows. A Tale of Terror by Adam Gauntlett. A Call of Cthulhu scenario by Jeffrey Moeller. An Arcane Artifact for Delta Green by Bret Kramer. A Mysterious Manuscript by Dan Harms. An Arcane Artifact by Dion Clark. A fascinating historical feature by Dave Hardy with Adam Scott Glancy. A Delta Green feature by Adam Scott Glancy. A Call of Cthulhu scenario for Delta Green by James Haughton. (Winner of the annual Delta Green Mailing List Shotgun Scenario Competition.) Short fiction by Greg Stolze.The Unspeakable Oath 20 features cover art by Todd Shearer, interior art by Toren Atkinson, Rob Mansperger Jr., and Bradley McDevitt, and page design by Jessica Hopkins. It's edited by Shane Ivey with Adam Crossingham, Dan Harms, Greg Stolze and John Scott Tynes.