This article presents some of the results of the MASTER Global Robotic Network over the past few years. But it begins with a theoretical substantiation of the main goal of our research - the study of extreme phenomena of the Universe. We are talking about processes that, in terms of their power, approach the power of the Big Bang and go into the modern era. Our optical observations are always part of multi-wavelength international research. We are talking about the first registration of Orphan optical flare at the growth stage (AT2021lfa), the discovery of a new observatory MASTER-OAGH in Mexico, the study of the brightest and most gamma-ray burst in the entire history of their study, extreme GRB 221009A. We talk about the Three-stage Collapse of the Long Gamma-Ray Burst from GRB 160625B model, multiwavelength study of the flat spectrum radio-quasar NVSS J141922-083830 covering four flaring episodes and Huge FRB monitoring by Global MASTER-Net during the COVID-19 pandemic , about probing into emission mechanisms of GRB 190530A using time-resolved spectra and polarization data, about exploring the early afterglow of GRB 190829A. In conclusion, we discuss our proposed optical candidate for a high-energy neutrino source. We have discovered the effect of a rapid decrease in the brightness of the blazar PKS 0735+17 at the time of the unique multiple detection of the high-energy neutrino IceCube-211208A.