Four Against the Great Old Ones is a horror adventure game for 1-4 players with an optional referee, but it seems mostly aimed at solitaire play. The game uses simplified tabletop RPG mechanisms to represent exploration of yog-sothothery in 1920s America. A single standard die (or even a marked hexagonal pencil) suffices for all randomization in the game, and a single sheet of paper can track all the characters. A full campaign can play out in a single sitting.

The setup allows for choice of four different character classes out of a field of eight, and places these investigators in a random US city to start their expeditions. Activities have a cost in days, and characters need to determine and arrive at their final encounter (which varies among a set of diverse Old Ones) before forty days have passed on the calendar.

The first thirty pages of the book present character creation and basic mechanics for play. The remaining fifty give information on the locations and encounters--effectively one big branching scenario. There are lots of entertaining details, and the lore of the game is entirely drawn from the literary corpus of Grandpa Cthulhu and his disciples--it is insulated from additional game "mythos" elements, particularly those built up in the Chaosium and Fantasy Flight games that dominate the Cthulhvian gaming scene. Still, the flavor is more pulp adventure with Lovecraftian foes than it is weird horror.

The prescribed method of play is to mark the book with a pencil as a record of encounters already accomplished and actions no longer available, and then to go erase all those marks before the next play. But there is an "encounter checklist" page that can be copied instead (or mocked up freehand--it's very simple).

During my first play, I only visited five of the sixteen mundane locations, plus a trip to the Dreamlands for one of my investigators. I didn't exhaust the encounters for any of those locations, and of course I only got to sample one of the six final encounters. As it turned out, my larger itinerary starting in Chicago brought me to R'lyeh for the Cthulhu final encounter. My team (occultist William Wesley Wakeman, spy Lizabet Solventi, detective Terry Sturgeon, and medium Madame Lemuria) overcame all the foes there for encounters 1 through 6, but exhausted the possible encounter roll bonuses without getting that necessary 7. So I resigned... to the inevitability of my characters succumbing to endless cultists and weird architecture. It was nearly a draw, certainly not a win.

There is clearly a lot of re-playability in this little book, and I'm sure I will return to it.