Nice work, really cool atmosphere and vibes! Echoing another comment, the areas, especially the first, are really big but there isn’t much reason to explore, especially since it take a while to get the sword. It was also pretty punishing on how easy it was to go straight to the boss and miss the save point. I didn’t really jive with the combat, mostly skipping all the enemies. I gave up after a few tries on the second boss, I couldn’t figure out a good strategy for him. There where a number of places where the interact prompt was really fiddly, it was always a little dance to actually activate the switches. Also, I really missed not having a shadow, I definitely am used using shadows to judge platforming but the light around the character mostly worked. Ultimately the platforming wasn’t a problem so maybe it doesn’t really matter.
Overall I think you have a solid core here, great job!