We began by experimenting with the Mixed Reality headset to explore which effects and interactions feel most convincing and immersive. This hands-on exploration allowed us to identify core elements that create presence and engagement in MR environments. Building on these insights, we developed scenarios specifically relevant to urban planning, focusing on how immersive tools can enhance decision-making and spatial understanding. The process culminated in a first prototype, created with Unity and tested on the Meta Quest Pro, demonstrating the potential of MR in shaping future city planning practices. The scenarios included where an intro/historical, an apartment situation, a facade selector and a park situation where one could create his own park.