Location of Zhúlóng (orange star) compared to the SFMS in the SFR–M_⋆ plane. The red-filled circles show three spectroscopically confirmed ultra-massive galaxies (Xiao et al. 2024). Error bars correspond to 1σ uncertainties. The extrapolated Schreiber et al. (2015) SFMS at z = 5.2, 1σ scatter (∼0.3 dex), and a more extended typical scatter of 0.5 dex are highlighted with a gray line, a dark gray-shaded area, and a light gray-shaded area, respectively. We also plot the Popesso et al. (2023) SFMS at z = 5.2 with a dashed line.