 Key developed the game using a game engine he had written in the C # programming language . The developers expressed interest in allowing player @-@ created mods of the game ; some such modified versions of the game have since been created by the community . After David Kanaga joined the development team as audio composer , the audio mechanics were refined through many different ideas , such as allowing players to create their own music within the game . This idea was cut because the developers felt it would detract from the exploratory emphasis of the game and turn it into more of a creative tool . 
