Emission-line ratio maps for the extended gas around PDS 456. Top panel: [N II]/Hα emission line ratio map, at S/N_Hα > 2.5, whose pixel size is five times larger than the native pixel in NFM MUSE data, which corresponds to ∼1.3 FWHM_PSF. The black dot gives the position of the central quasar, and has the FWHM size of the PSF_NFM. Bottom panel: Map of the [O III]/Hβ line ratio estimated through the [O III] and Hβ optimally extracted NB images extracted from the WFM MUSE data with CubExtractor. The black contours represent the S/N levels of the Hα emission extracted from the NFM MUSE data at 3, 5, and 10.