Design games are rarely used to design shoes but data and emerging digital fabrication systems are rapidly changing how designers make things. We envision a near future where shoes are personalised using algorithmic, parametric, and generative systems that are data-driven. In this article, we describe and deploy a design game for shoes to help designers create circular Ultra-Personalised Product Service System. Designing such products (that include services supported by systems that last over product lifetimes) presents a multitude of challenges; product challenges in negotiating design considerations, service challenges in customer journeys and systemic challenges in creating data flows. The UPPSS game was designed to help scaffold designers in confronting these challenges. The UPPSS game was deployed with 16 industrial design students over nine weeks where shoes, services, and systems were all made using code to program personalisation systems. Each participant wrote a reflection on the process. The reflections were analysed to see how the design game resulted in facing the challenges and learnings of a UPPSS. Conclusions are presented from the challenges and opportunities confronted in the game, and what it meant to the emerging practices of designing a UPPSS.