Original Idea, neat execution, a tad too slow
Here´s what I liked:
1) The split screen. A really good idea, this opens up a paralell world! You used it as a sky, others could use it for something else. The two screens wouldn´t always have to be connected in an "euclidean" (look it up, guys!) fashion.
2) The demonic stuff your demon walked over was also really cool. It seemed alive somehow. I would have appreciated a little more flashy graphic for this one since you end up staring at this black stuff most of the time.
What I didn´t like:
1) The game started out too slow and too easy in the beginning. And then suddenly gets really hard, around 248m. I wasn´t really paying attention until i saw those soldiers drop out of the sky. And it was the bomb that finally got me.
2) No "save", or "continue" points. Now, since I know what to expect, am I to play another tedious 248m until that first attack? Please install something like that.
Still, you get 5 for originality.