The game is awesome(one of the bests I have seen around here) and the art is even more awesome but I think it doesn't fit well on the theme. Anyway, I liked the difficulty, it reminds me of souls like and it's a pretty solid game. You should work more on that and release it some day, but maybe remove the one hit kill and add health to the character and checkpoints aswell(dying and restarting all the way is kind of lame) Overall is a great game but I had to give few starts to the theme rating.
Try it out my game, it has some difficulty aspects like yours!