If you’re not scared, you will be. A new virtual reality horror game uses the player’s heart rate to gauge how scared they feel, and if they’re not scared enough, it intensifies the horror.

To play Stigma, people use a virtual reality headset and a heart rate sensor. Players make their way through dark and creepy corridors. If their heart rate increases after coming across unexpected dead ends and creatures scuttling around their feet, the game takes that as a sign they are scared enough and continues unaltered.