Snapshots of the most massive cluster (﹩M\simeq 8\times 10^{14}\,M_{\odot }﹩) in the simulation at ﹩z=0﹩. Upper left, dark matter; upper right, gas particles; lower left, DM cores; lower right, cold gas. Circles in lower panels indicate the positions of galaxies identified according to our criteria. The comoving size of the box is 6.25 h⁻¹Mpc per side.