The game is very challenging, and has no tutorial. It is the kind of hard I prefer. This game was fun and interesting. The music was one of the things that stood out more than its graphics and physics, but I see this as an underrated game. I think a lot more people should play this. However, I can see that other reviewers could find this way too hard, way too easy, or downright confusing. I guess it could get better bosses and show a tutorial for beginner gamers.
I really enjoyed playing this, and it deserves a 4.5 out of 5.