Dead Letter Protocol

October 1968. A survey team has vanished from a remote Soviet research station. You have one night to search the station, recover its classified report, and find out what’s speaking from below.

Explore six sectors and 18 locations. Collect field records, use their clues to solve puzzles, and decide how to respond to the voice. Your final choice leads to one of three endings.

A single-player analog-horror mystery. First playthrough takes approximately 25–35 minutes, depending on reading and puzzle-solving pace. The game runs in a modern browser and saves progress on that device.