Left panel: cumulative distributions of host halo concentration for Symphony hosts (solid), Symphony hosts that are virially relaxed according to the Ludlow et al. (2016) criterion (faint solid), GALACTICUS realizations (dashed), and Erebos halos (black dashed) in the LMC (pink), Group (green), and Cluster (red) mass ranges. For the LMC and Group suite comparisons, we only use Erebos halos that satisfy our hosts’ isolation criterion. Right panel: median host-to-host concentration scatter, measured as the standard deviation of the ﹩\mathrm{log}c﹩ distribution in dex, vs. median concentration for jackknifed samples of Symphony hosts (circles), GALACTICUS realizations (squares), and Erebos halos (triangles) in the LMC (pink), Milky Way (blue), Group (green), L-Cluster (gold), and Cluster (red) mass ranges. Error bars indicate 1σ host-to-host jackknife uncertainties.