Occurrence rate of radio relics according to TNG-Cluster as a function of primary cluster mass (top) and redshift (bottom). The data points are colored based on different luminosity cuts, and the error bar shows the Poisson noise. The top subplot quantifies the number of clusters in each mass bin (black histogram) and those hosting radio relics above a certain radio luminosity (colored histograms). The final bin includes the three clusters with M_500c > 10^15.2 M_⊙. In the redshift distribution, the dotted and solid lines mark the clusters with M_500c > 10¹⁴ M_⊙ and M_500c > 5 × 10¹⁴ M_⊙, respectively. The fraction of clusters that host radio relics increases with the system’s mass, whereas the redshift dependence is less unclear.