The top panel uses the same background and markers as Figure 5, but focuses on the Serpens region. Light blue dots mark stellar members of the Serpens association from R. Kerr et al. (2023). The bottom two panels show the integrated extinction across two distance ranges in the G. M. Green et al. (2019) maps against the progenitor candidates, showing that two clouds share this line of sight: a closer one at around 250 pc that contains the westernmost HH objects, and a more distant one connected to the main Serpens clouds at around 450 pc.