Fract OSC (stylized as FRACT OSC) is a music-based puzzle game created by independent game developer Phosfiend Systems. The game was released on 22 April 2014 for both Microsoft Windows and OS X platforms. Fract OSC allows players to explore an abstract landscape that includes puzzles using platforming and music-based game elements. Completing these puzzles creates ambient music that continues to play in the environment and unlocks portions of an in-game music synthesis that allows players to create their own music.