Nice game! The music was great and really added to the game, and the idea was definitely in tune with the limitation of the jam.
I struggled a little bit to enjoy the game-play though, as I found myself clicking a giant skull what felt like a thousand times. Maybe giving a damage-increasing buff could do the trick, or just lowering its health! Another thing that bothered me was that the knife being swung from the back was unexpected, and at first I even thought it was a bug. That only added to the feeling that the weapon itself was pretty much the worst one, which made me just don’t even try to get the buffs in order to avoid getting it. Lastly, I also wanted to mention the lack of a health bar, but I read your comment saying that it was a bug, so that’s fine. Seven days is very little time to find those pesky bugs!
All in all, good job with the game though. I don’t mean to discourage with the previous paragraph, but rather give you all some honest feedback you could use! To make a game in only a week, with the amount of features you added, is a remarkable achievement! :)