How the TNG-Cluster satellite gas mass varies with the satellite stellar and host halo mass. Top left panel: for the ≈90 000 TNG-Cluster satellites with $M_{\star }^{\mathrm{sat}}>{10}^9{M}_{\odot }$, the fraction of satellites that retain gas reservoirs $M_{\mathrm{gas}}^{\mathrm{sat}}>{10}^9{M}_{\odot }$ today as satellites is shown in bins of satellite stellar $M_{\star }^{\mathrm{sat}}$ and cluster $M_{200\mathrm{c}}^{\mathrm{host}}$ mass. Top right panel: only 10 000 (10%) of the TNG-Cluster satellites retain gas masses $M_{\mathrm{gas}}^{\mathrm{sat}}>{10}^9{M}_{\odot }$ today. For these gaseous satellites, we show the median satellite gas mass $M_{\mathrm{gas}}^{\mathrm{sat}}$ in bins of satellite stellar $M_{\star }^{\mathrm{sat}}$ and host halo $M_{200\mathrm{c}}^{\mathrm{host}}$ mass. Bottom panels: we show the fractions (left panel) and numbers (right panel) of satellites with all (purple, solid, filled), hot (red, dashed, “\” hatched), and cold (blue, dashed-dotted, “/” hatched) gas masses > 10⁹ M_⊙ within a given stellar mass bin at z = 0. We mark 100% and the global average of 10% with black lines, and include the total number of gaseous satellites in the legend. While a given satellite is more likely to retain gas if it has a higher stellar mass, a given gaseous satellite is more likely to have a lower stellar mass because there are simply more lower-mass satellites.