The urban game TabulaRosa was experimented by Polimorph as support structure to stimulate the invention of possible futures together with a variety of actors towards the transformation of our living environment. Looking back at seven productions of the urban game either as cultural event or within urban planning and architectural design projects, this presentation will explicate why distinguishing play and game is relevant for transversal design and what opportunities and risks do occur when applied to participative design processes. What kind of transformative power do play and game have on our living environment? What is the impact of the gaming environment on pleasure, for socially robust knowledge and abuse of power? How do player mechanics anchor visons in a place and stimulate the imagination of new worlds? Play and game as a framework for collaborative design processes raise questions about collective decision taking and the empowerment of stakeholders who are usually further away from decision taking and action. Game boards frame the conditions for how to play. Can they become turning tables to alter the relationship between the players, to create a better equilibrium between the powerful and the powerless?