Ok this one is fun and you can start on other achievements here as well too. When you blow down the gate to visit Larry, he will give you a special mech that you have to use to destroy the cars in the parking lot. There will a ton of monsters that attack you everytime you use the missle laucher part of the so be carefull. You need to be sure that you destroy every single car in this parking lot. You also need to get the cars in the begining of the level where you first start out. Also you need to get the big truck by Larry's Garage. You also need to get the small truck hidden on the very left side of the mall hidden in the small side of the building. Once you get them all the achievement will unlock. Be sure that you go back to Larry's Garage frequently to buy helath packs. I suggest going back once you are at 3/4 loss of health.