Extended emission surrounding PDS 456, within the region of the WFM-MUSE FoV indicated by a dashed white box in the left panel of Fig. 1. This RGB composite image is generated from the following images: optimally extracted narrowband images of Hα (R) and [O III]λ5008 Å (B) obtained using the CubEx tool, and the white-light image (WLI; G). The black cross symbols indicate the line-emitting companions detected with the Keck Telescope (Yun et al. 2004), ALMA Bischetti19, and in this work with MUSE (see Table 1 for details). MUSE continuum sources are visible in green. The white contours show the surface brightness levels of the [O III] nebula at 10, 50, 100, and 500 10⁻¹⁸ erg s⁻¹ cm⁻² arcsec⁻².