OnlySP: Tower defense games are an interesting breed. They have been around since the the release of Atari’s Rampart back in 1990, but are still struggling to really find their place in the modern gaming world. With so many tower defense mods available for games like Starcraft 2 it can be hard for developers of this rather niche, genre to get any attention. Some developers try to differentiate themselves by including interesting twists on the standard tower defense formulas, such as the FPS elements in Sanctum 2. Others just try to polish the formula to an extent far beyond the efforts of other developers to set themselves above, rather than apart from, the opposition. Prime World: Defenders does a bit of both by adding in a couple of twists to the generic tower defense gameplay, but also trying to achieve a really polished feel.