Abstract: In this talk, I will discuss lamppost models where MeV to few GeV dark photons (A') couple to a dark sector with multiple generations of fermions with dark matter candidates or heavy neutral leptons. I will focus on the semi-visible signatures of A' (charged particles + missing energy) at fixed targets like NA64, e+e- colliders, and neutrino detectors. In addition to finding models that can still account for the discrepancy in the muon g-2, I will also discuss connections to neutrino masses and opportunities for future searches.