As human beings most of us are accustomed to relying on our eyes to see the objects around us and guide us to where we need to go. But that’s not the only way of perceiving our environment. Devil’s Tuning Fork is a free PC download developed by a small team of students from DePaul University. Highly experimental and set in an abstract world inspired by the art of M. C. Escher, the game attempts to let the player experience what it’s like to "hear" the environment instead of see it.

A small town is alarmed when its young children all start slipping into comas. One child (you, the player) awakens inside a claustrophobic alternate reality meant to represent the fevered mind of one of the comatose children. The world is pitch black, and the player must navigate with the help of a magical tuning fork in order to find the cause of the epidemic.

The tuning fork grants the player the ability to emit sound waves, which appear as monochrome stripes as they bounce off of walls and scenery briefly revealing parts of the shadowy world such as walls, stairs and platforms. The effect is similar to how bats use a phenomenon called echolocation to "see" where they’re going in dark caves.

The game is presented in first-person perspective and controlled using a combination of the WASD keyboard keys to move around and the mouse to look in different directions. You’re thrown into the experience with very little preamble or instructions, so the effect can be quite disorienting until you’ve gotten a hang of how the unique control scheme works.

Once the trick of bouncing the tuning fork’s sound waves off of the environment to look around and move is mastered, it becomes apparent that Devil’s Tuning Fork is at heart a simplistic platformer with moving platforms to ride, crumbling floors to avoid (by emitting a special low-frequency pitch on the tuning fork that can detect the faulty bits), and swinging hammers and blocks to dodge. The goal is to collect all of the stuffed animals in each area to free other children, and figure out how to get the door to the next area to open.

The fact that the game relies on puzzles and exploration rather than weapons and person-to-person combat is refreshing. Players who are prone to motion sickness should beware, however, as the undulating effect of the sound waves on striped, cavernous walls can be disorienting.

To enjoy Devil’s Tuning Fork is to experience it with an open mind, since the premise is really designed to be thought-provoking rather than fun. The atmosphere is intentionally dark and claustrophobic, the music is sparse and hauntingly beautiful, and the audio (which consists of disembodied voices in obvious distress) is unsettling.

Taken for what it is – a free download that pushes new boundaries in the ways players navigate through interactive entertainment – Devil’s Tuning Fork is absolutely worth a look, in spite of the fact that it might go over the heads of a lot of gamers who have been conditioned to expect more traditional or user-friendly experiences.