The MUSE blind surveys over Extragalactic Legacy Fields with excellent space imaging have vastly enhanced our view of Emission Line Galaxies across cosmic times. Thanks to the lack photometric pre-selection and a “spectroscopy of everything” within the MUSE Field of View, we are able to get an unbiased view of the star forming galaxies. I will highlight some of the science both at high and low redshift using mainly the MUSE-Wide and MUSE-Deep surveys in the GOODS-S and COSMOS areas. These include: clustering analysis of Lyman Alpha Emitters (LAEs), the steep faint end LAE luminosity function and characterization of high equivalent width sources reaching very low stellar masses. I will finish with some physical characteristics of the CGM in emission in galaxies at redshift ~0.7, thanks to the enormous sensitivity of the MUSE instrument.