Get ready for Halloween with this short but frightening indie game.

It’s never what people see that truly terrifies them. Rather, it’s what they can’t see. No matter how horror is delivered to you, rather by a book, movie, television show or video game, letting an unknown terror fester in the audience’s imagination will leave you more terrified than any grotesque imagery ever could. This is the idea behind Slender: The Eight Pages, a very short indie game available for free that is based around Generation Y’s envisioning of a modern day bogeyman, Slenderman.

Slenderman is one of the more interesting creations to be birthed from the hive mind of the internet. A inhumanly tall, suited figure with long arms and a featureless face, he was first envisioned as part of a photo editing competition on Something Awful a few years ago, and since, Slenderman has become a subject of art, spawned a number of online video series, and has had an entire mythos regarding his exact nature and intentions created, including an apparent penchant for abducting children.

In the game, you find yourself alone in the middle of a closed-off wooded area at night, holding only a flashlight. As you wander aimlessly around the area, you begin to notice landmarks strewn about, until you make the discovery of a note with hastily scribbled words and drawings: “CAN’T RUN.” “HELP ME.” “DON’T LOOK OR IT TAKES YOU.”

As you find the notes, a fog begins to roll in and a pulsing noise in the background begins to exponentially grow louder, and you start to realize that you’re being pursued. You can run, but only for a short while, and as the unseen Slenderman begins to draw closer bits of static begin to flash across the screen, accompanied with a piercing white noise. To escape, you must find all 8 of the notes across the landscape before your time runs out.

While the graphics are decidedly less than impressive, they also don’t need to be. Slender plunges you into the heart of what terror really is, and in the exact situation that our primitive brain fears most: lost, confused, and hunted. And it works. For a game so short and simple, it has become a phenomenon that leaves few players feeling safe and at ease after playing, inspiring a number of YouTube videos of people playing Slender, all of which typically end with screaming.

Slender: The Eight Pages is available for free download on the developer’s site.