Ok, As someone who beated games like Cuphead or Spelunky with 100% achievements, I love this kind of challenges. Your game is up to the task. Reeeeally hard, sometimes even unfair, but after some practice I manage to reach the boss second phase. Problem here is... he NEVER dies. I mean, I been shooting at him for 2 completely song loops, and the Son of... keeps attacking with the roots. i even try to shoot the roots, nothing happens, try to go to the upper platforms, instantly died. I was for over a complete hour trying to beat him, but no luck. Even manage to reach him with 3 lives! But in vain.
Apart from this, you made a GREAT work. Of course, always room for improvements (as other comments mention) but for a week game I think your game is one of the best in the jam.
The Art is AMAZING, the controls respond very accurate. I'm not completely ok with the mouse aiming, at least for this game, but maybe you manage to make it work in a fun way after the jam ends.
Very good job! Congratulations!
Please check mine if you can 😁