Earthquake source physics involves multi-physics system across scales, which has been studied by multidisciplinary approaches such as rock physics, field observations, geodetic and seismological measurements, laboratory experiments, and numerical modeling. Each research framework has made great advances in understanding rupture processes from long-term fault deformation to dynamic rupture propagation. The role of fault geometrical complexity, and its associated damage, are increasingly being recognized as playing a key role in understanding fundamental earthquake physics. The aim of this session is to bring together these disparate set of disciplines in one session and address the role of off-fault damage in the long-term fault deformation, spontaneous rupture nucleation and propagation, and the overall energetics of earthquakes.