My one complaint is that the different races you play as are not introduced as far as their abilities goes. Just started teh weird alien race and surprise, all of my turrets shoot rockets? That would have been nice to know before I built them.
Awesome game, except that to get gold stars on wave 3, you have to get really lucky with how the aliens come at you, otherwise they will kill you while you are turning to meet them.
 "Obliterate Everything"){kind=icon}
 "Desert Moon"){kind=icon}
 "Learn to Fly 2"){kind=icon}
 "Roadkill Revenge"){kind=icon}
 "The Eternal Battle"){kind=icon}