This is an amazing game, it's so impressive that you made something like this in just 10 days. I really enjoyed it.
The art, music and the atmosphere you created using particles and lighting, it all fits together so well
The last boss was so hard I couldn't beat him, but the fighting him was so fun, maybe you could add an option to heal? that would've helped with beating him, couldn't quite figure out the parrying but that just takes practice.
I'd really like seeing a full game of this!
Good job!