In this challenge you will take control of the Landstalker. Aim at the Quasar Orb and start firing your guns and mortars at it until it breaks, allowing you to pass. Up ahead you will have to fight a lot of DZ Strikers, Swarmers and DreadZone Dropships, but if keep firing away with your weapons and if you keep moving you should not take too much damage. Charging your mortars and releasing them at it should easily destroy it. At the next Quasar Orb, a Stalker Turret will be waiting to fire its guns at you. This one doesn't have a shield; however, so charge up your mortars while avoiding most of its fire will reduce the damage until you can destroy it.
Destroy the Quasar Orb and move up the hill. There will be a few Strikers which should be no match, but here you will find a dropship that doesn't actually drop troops but instead fires devastating rockets at you. Make sure this is your first priority when using your mortars, so that it will not affect your health as much. Take out the Quasar Orb, but prepare to take out another rocket-firing dropship up towards the arena. Get rid of the rest of the Strikers and if you keep moving towards the beam in the middle of the arena, then you should be fine. Once you reach the beam, you will complete the challenge.