Like charliejames4, I'm surprised War Rock wasn't mentioned here. This is a great freeware game that touts decent graphics, numerous weapons and good maps. It's built on the "freemium" concept though; better weapons can be rented. Here's my articles about War Rock Maps and Weapons: http://imbacore.blogspot.com/search/label/War%20Rock Also, UFO: AI should have made it in; that Quake 2-powered X-com clone is very solid.