There are few games that I find myself unwilling and unable to complete. This is one of them. It has an interesting mechanic of territory control (pushing shadows back with your imaginary tower-friends), and it creates a nice sombre tone with its cut-scene art.
However, it is ultimately a tower defense game that lacks player-friendliness and failed to have an impact on me. Skill points that you allocate are absolutely permanent. If you find yourself unhappy or unable to progress because of your skills, you'll have to restart the game from scratch to repick your skills. Further, winning battles leaves me unsatisfied, and I'm more irritated than distraught when I lose my units, little yellow plushies with no personality. The cut-scene art is nice, but the inexpert voice-acting can be grating if you pay attention to it.
Lastly, installing this game means you have to install Quicktime as well. This is how the game plays its cutscenes. It's pointed out in the requirements (har har as if we read those), but if you have the same hate on Apple I've noticed in some Steam threads, then this is just icing on the "Try something else" cake. I only recommend this game to hardcore tower-defense game enthusiasts who enjoy skill-picking with no backtracking, and who do not listen to cut-scenes.