Minecraft led to Persson becoming one of "Forbes" "World's Billionaires". "Minecraft"s music and sound effects were produced by German musician Daniel Rosenfeld, better known as C418. The background music in "Minecraft" is instrumental ambient music. On 4 March 2011, Rosenfeld released a soundtrack, titled "Minecraft – Volume Alpha"; it includes most of the tracks featured in "Minecraft", as well as other music not featured in the game. The video game blog Kotaku chose the music in "Minecraft" as one of the best video game soundtracks of 2011. On 9 November 2013, Rosenfeld released the second official soundtrack, titled "Minecraft – Volume
Mojang Using "Minecraft", the community has helped reconstruct the areas of concern, and citizens are invited to enter the "Minecraft" servers and modify their own neighborhood. Carl Manneh, Mojang's managing director, called the game "the perfect tool to facilitate this process", adding that "the three-year partnership will support UN-Habitat’s Sustainable Urban Development Network to upgrade 300 public spaces by 2016". Mojang signed "Minecraft" building community, "FyreUK", to help render the environments into "Minecraft". The first pilot project began in Kibera, one of Nairobi’s informal settlements, and is in the planning phase. The "Block By Block" project is based on an earlier