Thanks for the detailed feedback, the notes were very pertinent.
Many of them are things that due to the Jam time I didn't have time to adjust or balance (like the enemies time reward too high for example), others are bugs that I'm already fixing in the latest version (like the skulls appearing without warning) .
As for the sound and music, I did everything improvised because I'm not a musician, but I intend to find someone competent in this area who can make a more pleasant sound.
The game is based on "fight, die, learn and repeat", using the idea of looping as learning, so the villain having an attack that kills on the spot without indication is part of this process, but I understand when you say it can be frstrating, I'll see if I make him more threatening or with more indication of how dangerous he is.
I will consider all of his comments for future updates, thank you very much! :)