Whenever the tops gets going, you need to be tough and rise to the occasion. In a war situation, you need to stand up your ground or the enemies would seize your outpost. In this game, you control an outpost and you need to defend it against attacking enemies. Each kill would earn you money that you can use to buy defense to your base. Nothing gets easier since the more you advance, the tougher your enemies gets. The game would be harder and the enemies would get tougher as you make some progress, but that is where the excitement comes.