| System (Setting) | Publications | Articles |
|---|---|---|
| Raiders of R'lyeh | 3 | 24 |
| Raiders of R'lyeh | 3 | 1 |
| The Rats in the Walls | 1 | 1 |
| Reanimator | 2 | 2 |
| Recall of Cthulhu | 1 | 1 |
| Red Bat | 1 | 0 |
| Renaissance (Dark Streets) | 5 | 2 |
| Ressurection of the King | 1 | 0 |
| Rise of Cthulhu | 2 | 2 |
| Rise of the Elders | 1 | 1 |
| Risus | 2 | 2 |
| Rites of Cthulhu | 1 | 1 |
| Runequest | 1 | 0 |