Los años de la Gran Depresión y la época por defecto de El Rastro de Cthulhu.
| ▲Título▼ | △C▼ | ▲Año▼ | Autor | ▲V▼ | ▲Rel.▼ |
|---|---|---|---|---|---|
| NPCs |    ? | 2008 | Adrian Bott, Simon Carryer, Jérôme Huguenin | — | Media |
| Occupations ("Trail of Cthulhu Keeper's Screen & Resource Book") | | 2008 | Adrian Bott, Simon Carryer, Jérôme Huguenin | — | Media |
| The Thirties | | 2008 | Ken Hite | — | Alta |
| Thirties London | | 2010 | Ken Hite | — | Alta |
| Appendices (to "Beyond the Mountains of Madness") |   | 1999 | Marion Anderson, Phil Anderson, Charles Engan, Janice Engan, John Goodrich, Steve Hill, Mike Lay, Mike Blum | — | Media |
| Chapter 4B: SS Gabrielle | | 1999 | Mike Blum, Charles Engan, Janice Engan | — | Media |
| Alone Against the Dark |    | 1985 | Matthew J. Costello | — | Media |
