Ecocraft is a computer game, as well as an educational tool, as well as a citizen participation tool, developed for joint creation of sustainable urban spaces. The virtual environment of Ecocraft is created by digital twinning the real world into the virtual world of the popular computer game Minecraft. The gaming environment of Ecocraft is based on accurate geospatial data of the real world and utilizes impact models and future scenarios to simulate and visualize future developments and their implications, providing the user with relevant information during the game / the design processes. The objective of Ecocraft is to raise environmental awareness among children and youth, particularly about their surrounding environment and its processes, as well as the human impact on the environment and the need for sustainable resource management. Ecocraft players will aim to design the city in a way, which enables creating friendly, green spaces that harmoniously combine the city's components - architecture and infrastructure, transport, the needs of local communities, public space, climate conditions and resource availability. The city should meet the expectations of different groups of users by responding to their needs.