Turtle Rock Studios  Turtle Rock Studios, formerly Valve South, is an American video game developer founded in March 2002 by Michael Booth. It was acquired by Valve in 2008, but was re-founded in 2011 as an independent company by Phil Robb and Chris Ashton. Turtle Rock Studios is involved in the creation of original titles as well as the provision of consulting services to the digital entertainment industry. The company's most notable games are the first "Left 4 Dead", which was published by Valve, and "Evolve", which was originally set to be published by THQ but was later published by 2K Games. The founder of the company had worked for Westwood Pacific, and assisted in the development of the "Counter-Strike" series. The company expanded from six employees to more than seventy staff members from 2011 to 2014 and opened a subsidiary company called Turtle Rock Garage in 2011, which specialized in developing casual and experimental games for platforms such as iPhone, Facebook and Xbox Live. Turtle Rock Studios was founded by Michael Booth. Prior to the company's establishment, Booth, Phil Robb and Chris Ashton worked for Westwood Pacific and participated in the development of real-time strategy games like "". Ashton, who had also worked for Presto Studios, was impressed by "Counter-Strike", which was a popular mod of "Half-Life", and decided to join the mod team as a texture artist. Eventually, Seattle-based Valve, the publisher of "Half-Life", purchased the mod, and Ashton left Westwood to join Valve. Robb and Booth remained at Westwood Studios and worked on "" and "", but left the company after it was acquired by Electronic Arts, as Robb considered EA's acquisition of Westwood had resulted in the studio losing all its personality. Turtle Rock Studios was founded in 2002. The team of about six people had limited resources so set up work space in Booth's garage. The name "Turtle Rock" derived from the name of a neighbourhood where Booth lived. The team expanded the studio and rented an office, and continued the development of "Condition Zero". The game was released in 2004. Satisfied with the work done by Turtle Rock, Valve continued to contract them to work on the Xbox version of Counter-Strike, as well as the next installment of the series, "", and "". Upon the release of Source, the company wanted to work on a new game, and gained support from Valve. The team later chose to design a first-person wizard combat game. As the team had developed only competitive multiplayer games before, they wanted to design a game that encouraged and supported co-operative gameplay between players; a game that would allow family and friends to play together instead of against each other, citing "Secret of Mana" as an example.