When EPISODE THIRTEEN, my found-footage novel about a paranormal reality TV show, came out, I was asked in interviews about sources of inspiration for it. A big one for me was PHASMAPHOBIA, a computer game. This is the scariest, most enjoyable horror game I’ve ever played.

When I first heard about it, I was skeptical. The game’s graphics and game play looked pretty janky to me. You don’t have any weapons, which feels weird when you’re used to playing first-person games that have a combat element. You move slowly. Most of the houses you explore aren’t creepy mansions but instead regular suburban homes. What’s scary about this?

A lot, it turned out. It scared the crap out of me.

Okay, here’s how it works. You’re a member of a team of up to four professional ghost hunters. You travel to haunted houses and explore them to 1) locate where the ghost is, 2) identify the type of ghost based on the evidence you collect, and 3) do optional actions like get the ghost to blow out a candle or get a picture of it. The only problem is the ghost generally remains unseen, so you have to use a variety of detecting equipment to discover physical evidence the ghost leaves. Another problem is the longer you’re in the house and depending on what you say over the mic to the ghost or your teammates–the game uses voice recognition–the ghost starts to get agitated. This is good, as its activity leaves evidence, but bad, in that the ghost may decide it’s time to hunt and kill you. The lights flicker, the door slams, you’re trapped, and you have to hide and pray the thing doesn’t get you.

The detective work is fun, but what makes this game work is the atmosphere of dread–something I tried to bottle in EPISODE THIRTEEN–in this case achieved with darkness and subtly with sound along with your own willing suspension of disbelief. The moment you go into the house, you know you’re on the clock for the ghost getting angry. There are jump scares, but they’re sparse and earned, such as when you’re just about to leave the house and the door slams in your face, signaling the ghost is coming for you. Out of all the games I’ve played, this one comes closest to the experience of reading, where the player’s imagination does a lot of the work. Like watching a horror movie, if you tell yourself it’s only a game and doesn’t matter, it likely won’t affect you much; but if you run with it and let yourself be immersed, it will very likely freak you out.

PHASMAPHOBIA is a classic game that is virtually unique among horror games, though it has had many (poor in my view) imitators. I recommend it if you’re looking for a horror experience you can enjoy solo or with some buddies online.