Thus, it goes viral. When the phenomenon began peaking in late 2024, we at Ichor Weekly reached out to Chaosium’s PR department. Their response was… unsettling.

Do not open it.

Worse, the "chain letter" aspect is viciously effective. Because the PDF is genuinely useful. The one-shot scenario The Final Broadcast is widely praised by those who have played it as one of the best solo horror modules ever written. So, players forward it to their friends for the game content , ignoring the superstitious warnings.

But is this a genuine marketing stunt by Chaosium (the publisher of Call of Cthulhu )? A piece of viral alternate reality gaming (ARG) brilliance? Or, as the conspiracy theorists whisper, something… stranger?