A very good entry! I did a metroidvania for the Nokia Jam 4, and this is much better than mine was! It overall was well designed, and it felt very coherant. The major thing I can say is that the final boss doesn't have enough player feedback to tell if you've done actual damage to him. Besides that the text color is a pure white instead of the Nokia green, but that shouldn't disqualify the game in my opinion. There was also one jump towards the beginning that felt a lot like a "developer jump" to me (a jump that's stupidly hard, but because you're the developer you don't notice. My metroidvania had one as well XD). Besides that the game was very good. I especially liked how you limited it to only playing one sound effect at once to better emulate the nokia. Overall, amazing job!