I tried ghosts, and the only way to knock them out of the middle was by tipping them over with another ghost. I went with mongooses because it seemed to work better. Also, if the entire other team went defensive, they couldn't win. I've also tested all the weapons in the game and found the rail gun works the best(Rockets were too powerful, assault rifles didn't do anything, semi auto rifle did knock the vehicles in the middle, but not much, as well a they had a large clip). Rail guns were the best choice because they only have 5 shots. Thanks for the question.