There are continuing theoretical activities to understand experimentally observed unusual (not explained by the ideal MHD theory) stability of the Field Reversed Configuration (FRC) plasmas and the existence of the FRC-equilibria as a relaxed state. FRC plasma sustainment system based on high energy particles are proposed to exploit their possible good confinement. It is also proposed to realize pulsed fusion system with the particle density between continuous systems (~1020/m3) and inertial systems (~1031/m3); the magnetized target fusion (~1026/m3) and the pulsed high density systems (~1023/m3). With the aim of overcoming the limitation in producing large scale, continuous FRC plasma, theoretical and experimental studies are intensively carried out on the FRC plasma formation and/or sustainment by the rotating magnetic field (RMF). The technology of the translation made it possible to apply standard method of sustaining the plasma - the neutral beam injection and the wave - to the theta pinch produced FRC plasma. Except for the duration, this plasma has the best performance (density and temperature) and low frequency wave is successfully induced and propagated deep in the FRC plasma.