Thought Playdead’s Inside couldn’t get any creepier? Think again! The game’s sinister score was literally the sound of a human skull falling apart.

That’s according to sound designer Martin Stig Andersen, who’s presumably on a mission to become gaming’s most unsettling composer.

“I had the idea of working with a human skull because I think it’s very interesting how the sound of your own voice sounds very different in your own head,” he wrote on Gamasutra, apparently oblivious to how much he sounds like a psychopath. “That was the curious thought that led me to acquire a human skull and experiment with it.”

Sure, Martin. It definitely didn’t come from your private collection.

He took the game’s synth score, played it through the skull, re-recorded it, and applied some post-processing, for a result that he’s called “generally a bit creepy and cold.”

If you’re miraculously unsettled by all of this, then wait for his final, terrifying revelation:

“Eventually all the teeth fell out of the skull because of the vibrations, but while they were still there they created this small vibrating sound that I think was unsettling but also strangely familiar to people. Because we all know it, in a way.”