The light curve of the SN, shape as in Fig. 1 and the third peak from our toy model where we try to fit the third peak energy and time-scale using SN energy and mass from Wang et al. (2018). The other parameters are in the text (Section 4.2). The red line represents the contribution of the SN itself, the thin blue line represents the ‘mini-explosion’ of our toy model (the peak), and the red+thick blue line represents the total light curve with the peak. The green points are the data of the third peak of iPTF14hls (The Open Supernova Catalog), where the larger green circle on the bottom right of the peak is the general location of several close observations. t_L, t_j,0, E_2c, and E_2j,rad are the launching time of the two opposite jets, the ‘mini-explosion’ time of the jets, the energy that the two jets deposit to the cocoons, and the extra energy radiated by the two cocoons.