In the contemporary society, digital technologies emerge as a path for cultural heritage, emphasizing the need for accessible and inclusive experiences. This chapter explores a collaborative game design project aimed at enhancing accessibility and engagement with cultural heritage for People with Intellectual Disabilities (PwID). The project, developed with game design students, civil society stakeholders, and museum personnel, presents Bordalo e o Gato (Bordalo and the Cat in English)—a top-down puzzle and customization game inspired by the artwork of Rafael Bordalo Pinheiro. The game’s objective is to promote engagement by making museum content accessible in an interactive, inclusive format that fosters cultural accessibility. In the game, players help a cat named Pires reach its food, unlocking and using pieces of Bordalo’s iconic ceramics to create personalized objects, thus bridging academic work with public cultural spaces. The project adopted a qualitative methodological approach, grounded in principles of co-creation and participatory design. Ethnographic methods, including participatory observation and iterative playtesting sessions, were used to gather rich, nuanced data from diverse stakeholders. This inclusive research framework ensured that the voices and experiences of PwID were central to the game’s development, challenging traditional power dynamics in cultural production. The results revealed that the game successfully lowered barriers to accessing the museum’s collection, making the works of Rafael Bordalo Pinheiro more approachable and enjoyable for PwID. Key accessibility features, such as clear visual feedback, simplified mechanics, and adaptive difficulty levels, were instrumental in fostering engagement and empowerment. The customization module (called Gallery), which allowed players to create their own interpretations of Bordalo’s ceramics, was particularly effective in promoting cultural engagement and a sense of ownership.