Limbo is a puzzle-platform video game with horror elements developed by independent studio Playdead and originally published by Microsoft Game Studios for the Xbox 360. The game was released in July 2010 on Xbox Live Arcade and has since been ported by Playdead to several other systems including the PlayStation 3 Linux and Microsoft Windows. Limbo is a 2D side-scroller incorporating a physics system that governs environmental objects and the player character. The player guides an unnamed boy through dangerous environments and traps as he searches for his sister. The developer built the game's puzzles expecting the player to fail before finding the correct solution. Playdead called the style of play "trial and death" and used gruesome imagery for the boy's deaths to steer the player from unworkable solutions.