This game is a chore to play, I don't have fun playing it. It's too repetitive.
Take the first area. I'll have a very good game, take out all enemies and then die at the boss. As a result, I'm back at the beginning and I have to do the same thing all over again (the same enemies/challenges that I've already beaten). Yes, I can run past the enemies, but that first attempt at the boss used up all my blood vials, so I have to start killing the same enemies again (to gain more blood vials). This game needs more checkpoints. It's not fun killing the same enemies over and over and over again.
Frustrating game.