Illustration of the end-to-end mock X-ray analysis applied to TNG-Cluster to mimic observations with XRISM Resolve. We showcase the process described in Sect. 2 for a single randomly selected Perseus-like cluster for an exposure of 100 ks. In the top left panel, we first show the intrinsic X-ray surface brightness map of the simulated cluster, which is similar to those of Fig. 1, in which the central green square specifies the approximate FoV of XRISM Resolve (∼70 × 70 kpc). The top right panel then shows the count-rate map via the mock observation. Bottom: segments of the associated mock spectrum that resolve individual lines at the Fe XXV Heα complex, Fe XXVI Lyα, and Fe XXV Heβ, with the best-fit bapec model overlaid.