Every second, somewhere in the Universe, a star explodes and briefly outshines an entire galaxy. With new powerful sky surveys (e.g., PTF, PS1, CRTS, ATLAS, Gaia, ASASSN, ZTF, etc.), we are finding different varieties of transients and discovering a highly assorted zoo of observational properties. Amid all classes of SNe, superluminous SNe (SLSNe) is one of the rarest events. SLSNe exhibits W-shaped O II features in the bluer part of the near peak spectra. The field of SLSNe was utterly unknown before SN~2005ap, and nearly 150 objects have been spectroscopically confirmed so far and aspect of intensive study. It is also evident that only a tiny fraction (~1%) of stripped-envelope core-collapse SNe (SE-CCSNe) that produce Type Ic-BL SNe can produce detectable long gamma-ray bursts (lGRBs). Understanding these transients in their entirety is an evolving topic and challenges the current paradigm in stellar evolution. In my talk, I will discuss the photometric and spectroscopic evolution of H-deficient slow- and fast-evolving SLSNe (SN 2010kd and SN 2020ank) and possible GRB-SNe connections. I will also talk about a very luminous Type Ib SN possibly driven by a millisecond magnetar (SN 2012au). I will also discuss the Photometric calibration and characterization of the 4Kx4K CCD Imager, the first-light axial port instrument for the 3.6m DOT.