  We address multiboson production from a heavy $Z'$ resonance in the context
of the UN2HDM, a standard model extension with an additional $\text{U}(1)'$
symmetry and an enlarged scalar sector with an extra doublet and a singlet.
After taking into account theoretical and experimental constraints on the
model, it turns out this type of signals - mostly uncovered by current searches
- could be sizeable. We focus on three benchmark scenarios, each of them
predicting up to 4000 multiboson events with the LHC Run 2 collected
luminosity. Anomaly-detection methods could uncover those signals, if present
in data.
