Vehicles & Large Models Leviathon This tank has been in my collection for many years. Produced by Ground Zero Games, it has been the main battle tank for the Sovereigns for quite a while. Leviathon Main Battle Tank (model by Ground Zero Games) After all these years, the model could still do with some weathering, it looks far to clean.... The Leviathon is produced by Jon Tuffley at Ground Zero Games, a friendlier bunch of guys you just won't get to meet.