A bit strange to call it a tower defense game when you don't build towers and don't defend a tower, but nonetheless, it's a fun little horde game and I understand the naming despite the confusion. I had a good time for around 15 waves or so, but by then, it kinda wore thin as it didn't feel like the powerups or the levels or the enemies were expanding in significant ways fast enough to keep interest. Still, the game has a nice, all-together good feel to the art, sound, animation and design that I think with some additional content such as new mechanics, enemies, levels and such it could be really great!