The m-68 planetary magnapulse cannon was built with a large underground generator and a large rotating plasma cannon above the surface. The cannon fired plasma balls at the enemy vehicles, causing massive electrical disturbances that disabled the targets for a time.
Originally designed as a surface-to-space weapon, m-68 turned out to be more effective at surface-to-surface combat. The need for a surface-to-space weapon resulted in creation of the w-165 planetary turbolaser. Due to its high cost, m-68 was only deployed on a selected number of planets.