In this talk I will discuss photon spectra from annihilating Dark Matter. In particular the search for monochromatic lines is of great interest, as from the particle physics perspective it allows to determine the DM mass. And from the astrophysical perspective it is unlikely to be mimicked by a compact source. I will address the general question, under which circumstances in a given model a line is in principle observable given a finite instrument resolution. Two mechanisms which allow to see such gamma line features will be presented and the corresponding model realisations discussed. I will discuss how line searches open the window of possibility to scrutinise possible observed continuous gamma ray excesses. As concrete examples the Galactic Center excess and the Reticulum II excess will be considered.