Seed formation rate, J_* [cm⁻³ s⁻¹ ], that triggers the cloud formation (left axis) and the resulting cloud particle number densities, n_d [cm⁻³ ], (right axis, thick dashed line). The total seed formation rate (solid red line) is the sum of the nucleation rate for TiO₂ (solid blue), SiO (dashed brown), and C (dashed grey). Only TiO₂ and SiO form condensation seeds, carbon does not condense in the oxygen-rich environment of WASP-18b. No seed formation occurs on the dayside, therefore no clouds can form, except in the mid-latitudes near the east day- to nightside terminator.