Top: two-dimensional frame of the combined X-shooter nebular phase (+360 d) spectrum of SN 2016hnk after sky subtraction around the region where we detected the only feature. The trace can be clearly seen around 730 nm. The other feature around 750 nm is due to a bad telluric subtraction, since it is present along the spatial direction (vertical). Middle: combined 1D X-shooter optical spectrum showing the only two features detected in the whole UV+Opt+NIR wavelength range. Bottom: zoom-in to the feature we identified as being due to calcium emission. The blue and orange shaded regions represent the shift of ∼700 km s⁻¹ between the peak of the emission and the rest-frame wavelength.