Very cool theming, with great characters designs and a cool world, I was surprised to see how many little details you managed to cram in. I also liked having four different weapons with very different uses, I tried to adapt to each of the bosses.
I think the boss battles themselves need a little bit more balancing, as you can face-tank the majority of their attacks, which also sucks out some of the fun of alternating between weapons (as you can stand in front of the boss and go swinging your melee until it dies).
Overall though, very nice entry!