The symposium will provide an interdisciplinary forum, timely bringing together astrophysicists, computational and nuclear physicists, gravitational wave researchers and others to discuss these new findings and lay down the open questions to be solved in the first decade of multi-messenger astrophysics. It will present the status, perspectives and challenges in the blossoming era of multi-messenger astronomy and it will explore the many facets of magnetars, from theory to their most to extreme observational manifestations, cosmic fireworks, such as giant flares, gamma-ray bursts, kilonovae and supernovae. It will include discussions on next generation facilities for multi-messenger astronomy and their associated science cases.