Biodiversity hotspots exposed to increasing anthropogenic and climatic uncertainties, coastal areas provide excellent laboratories to study global change adaptations. Integrated coastal zone management, set-up as a replicable process, often fail to address challenging wicked issues. Indeed, simultaneous adaptations occurring at different scales or in different activity sectors often result in maladaptations such as vulnerability transfers that impede global sustainability. Addressing these transfers raise conceptual and practical issues. To tackle these, we ran participatory workshops in South Africa, with contrasted and often segregated stakeholders. The workshops started with fun care-giving and mindfulness exercises, to encourage dialogues and co-learning. Participants were then invited to play on a participatory device representing the multi-scale and multi-sector governance of coastal systems. Inspired by Anderies et al.'s (2004) Robustness Framework, the device was designed as a serious game in which players manage public infrastructures in response to contrasted environmental scenarios. In order to represent the decentralized aspect of the governance, each player was responsible for a given sector of activity with clear objectives at given scale and had to cooperate with the others to shape collectively future conditions on their territories. A simple algorithm computed the social, economic and environmental evolutions of the territory based on players' decisions. Combining experts' knowledge (practitioners and scientists) in the design of the game through pre-workshop interviews allowed to build a place-based game meaningful to local stakeholders. Serious games provide realistic boundary objects to grasp cross-sectoral and multiscale vulnerability transfers around global change adaptations. (Texte intégral)