In the Amazonian floodplains, artisanal fishing is a historic activity of high socioeconomic and cultural importance. In the last decades, fishing and fishermen have been suffering from numerous socio-environmental threats, compromising the ecosystem and its biodiversity, and local population livelihoods. Since the end of the last century, fishing communities have pressured the government, civil society, and other social actors to assume and support a sustainable co-management of fisheries in the region based on fishing agreements. It is in this context that we have been developing the construction of a roleplaying game called 'PescaViva'. Based on a companion modeling approach, the game has been built collaboratively, involving local fishermen/farmers leaders and environmental agencies representatives. Our aim is to develop a game that would meet not only the wishes of the research team but mainly the fishermen and people from the government. This paper describes how researchers, together with local actors, have worked on the challenges of the 'PescaViva' co-construction, considering the complexity of artisanal fishing in the Amazon and the scarcity of scientific knowledge about the activity. In some test sessions in the fishing communities, the game was understood, well-received, and associated with the local reality. It remains to be seen whether gaming sessions could be organized at the initiative of the local stakeholders themselves with the support of local facilitators in order to revitalize the dialogue and stimulate the construction and review of local fishing agreements.