Excursion set of temperature map for the fiducial model at z = 0 for different values of the threshold: whole field (top left), T ≥ 7 × 10² K (top middle), T ≥ 10⁴ K (top right), T ≥ 10⁵ K (bottom left), T ≥ 10⁶ K (bottom middle) and T ≥ 10⁷ K (bottom right). As for Figure 2, these maps do not include the additional Gaussian smoothing of 1.56 h⁻¹ Mpc and adopt the same colour code.