Without a doubt one of the best tower defense games. Good graphics, sound, towers. My main gripe is that the "easy, medium, hard" arent necessarily proper indicators for how difficult the levels actually are, especially in the first expansion, where the 3 medium levels are actually really hard and the "hard" levels are medium, if not outright easy. Also, not that theyre obligated, but I really wish they would add more levels. Id re-buy the whole game if theyd just write new levels.
TheStreisandEffect about geoDefense, v1.7