I love Tower Defense games, especially when you get to build your own mazes.
Gameplay: Reminds me of a better version of Xeno Tactics 2, where the concept remained the same as Xeno Tactics 1/Desktop Defense, but had updated graphics and level designs.
Graphics: Great. I kept thinking how this was made, because the towers themselves move as though they are 3D models, but could be sprites.
Audio: Wasn't anything too outstanding. I didn't mind it at all.
Difficulty: Way too easy in my opinion. It just took me a while to finish each level, but other than that, there wasn't anything that got in my way. I guess this is more of a starting point for novice players or players who haven't experienced the "build your own route" type of defense.
Improvements: Increased difficulty; each enemy should become increasingly difficult as you move to the next stage, whether you make them move faster, have more of them bunched together, or give them more hp. Better towers; there's a nice variety of towers in this game, but most of them I found pretty useless. The most expensive tower seemed no more effective than two plasma towers which cost a lot less if upgraded fully. There should be a bigger difference between each tower so there's a point of choosing one over the other.