Inside, the mysterious puzzle platformer by Playdead, continues the dark and isolating tone of its predecessor, Limbo. Much of the game's atmosphere can be attributed to the soundtrack, which offers a beautiful, yet haunting frame for the narrative. To nail this sombre mood, composer and sound designer Martin Stig Andersen turned to the human body. He found an old skull (yes, a real skull) and played the game's score through it, like an old school filter. The results were "quite bad," but Anderson persisted -- with a little post-processing, the final tracks were born.