Social robots have the potential to help people with mobility and coordination problems, especially in elderly people, in a fun and enjoyable way, as they can support physical stimulation exercises by enabling the gamification of games for this purpose. In this paper, we present a version of the computer game Pong as a serious game implemented as a multi-agent system, in which the social robot Mini guides the activity to promote the physical activity of the user. We track the user’s hands to replace the classic paddle game controller, facilitating the assessment of physical stimulation and hand-eye coordination. To improve the game’s engagement, the user can play against the robot, against another player, or against themselves. Incorporating gamification elements improves sustained user participation and skill development. The proposed system has been integrated into the robot’s software architecture, and preliminary tests show potential for promoting physical activity among seniors.