Self-consistent modeling of runaway electron (RE) transport in stochastic fields has been a long standing problem in the study of disruptions. In particular towards the later stages of the disruption, when the REs dominate the dynamics of the bulk plasma, the effect of the current carrying particles on the MHD cannot be neglected. However, the vast difference in time scales between the MHD and the transport of REs traveling close to the speed of light makes simulating such transients a difficult task. Recent developments in the JOREK code aims to allow for a more complete treatment using a kinetic model for the runaway population which has been coupled to the fluid equations governing the bulk plasma via a full-f particle-in-cell approach. Initial validation based on the drift orbits and major-radial force balance will be shown, along with a first application to a benign beam termination scenario in JET.