Top panel: comparison of the early g-band light curve of iPTF15dtg to the early light curves of other SE SNe and SLSNe that exhibit a double peak. For each SN the filter and the SN type is reported in the legend. The data for SNe 2006aj, 2006oz, 2008D, and 2011dh are taken from Brown et al. (2009), Leloudas et al. (2012), Bianco et al. (2014), and Arcavi et al. (2011), respectively. Bottom panel: absolute r-band magnitudes of iPTF15dtg compared to those of other well-studied SNe Ic from the literature. Data for SNe 1994I, 1998bw, 2004aw, 2007gr, 2011bm are from Richmond et al. (1996), Clocchiatti et al. (2011), Taubenberger et al. (2006), Hunter et al. (2009), Valenti et al. (2012), respectively.