Plazma Burst 2 H5 version is maintained by Eric Gurt, has better performance than Flash version (runs best in webkit browsers like Chrome, Edge, Opera, Brave), has Campaign and Multiplayer modes. Custom Maps functionality is still partial, especially when it comes to new maps.
Plazma Burst 2 Flash version is maintained by Lin and it is based on Eric Gurt's version. This version supports most features. It might not have the best performance due to Flash Player limitations.