Mojang 2012, Mojang was co-developing a video game codenamed "Rex Kwon Do" alongside an undisclosed developer. Before the title had reached a significant stage of development, Mojang cancelled the collaboration, due to their lack of involvement and influence on the project. In March 2012, Persson revealed that he would be designing a space sandbox game. Although Mojang teased with an April Fools' Day website based around "Mars Effect" (citing the Bethesda lawsuit), it was confirmed that the game was indeed in development, albeit with a different name. On 4 April, Mojang revealed the game's title to be "0x10", set in the
Mojang year 281,474,976,712,644 AD of a parallel universe. In April 2013, Persson announced that the game was shelved, due to a creative block. In August of that year, he claimed that the game was indefinitely postponed, with the incentive that other Mojang staff members could continue its production should they desire. In September 2012, Mojang began the "Block by Block" charity project in cooperation with UN-Habitat to create and design real-world environments in "Minecraft". The project allows young people who live in those environments to participate in designing the changes they would like to see and involve them in urban planning.