Wow, what a ride! As some others have pointed out, the game is very difficult due to a lack of knowledge of how much HP the player has. Also, having to invest HP in order to perform special moves adds to the problem.
I'd suggest introducing a separate resource to draw from to perform special moves as well as the ability to heal (maybe by drinking blood from fallen enemies). Because all in all, I'd love to be able to explore the levels you've built, but the difficulty is too high for me currently.