I was actually quite impressed by this game. While it could have had a wider variety of enemies, it was still well done. The best part about it was probably how it was easy to get a bunch of medals! Yes, I'm that kind of gamer. I actually did think that the graphics were pretty nicely done. Again, there just could have been more detail.
I find it hard to believe a building is that high. Then again, these are magic ninjas we're dealing with. The music was also nice and it fit the mood really well. My advice is that you should look for the hearts above all other things. I don't even really know what most of the other powerups do.