Cool game and unique levels, its really different than other popular TD games. Too bad the hero mechanics are flawed which makes some levels really hard (levels 11 and 12 are freaking hard). And rangers have no use in this game really. Also, rewards for achievements would be a nice addition to the game.
This takes too long, its glitched (invincible ninjas), and boss fights are too vague, and the speed special stops you from maintaining your combo streak