Artistically the game is, ON POINT! Cool art, music is super cool. I would personally keep the music going through the transitions instead of fading and restarting. That we I actually get to hear the full track while playing your game. The intro is super cool and immersive with the title going into the game!
With how good the music was SFX would have been really nice to have!
I think some of puzzles are actually clever ITO solving from a thinking perspective. However the actual execution from a player perspective was quite frustrating. Your puzzlesfelt difficult because the controls over your character's abilities felt clunky to use. There was always some sort of delay between trying to use an ability and my brain, but because the intrigue of the story/art it made me want to keep playing and struggling. Also, WASD and 123 are not super ergonomic I'd separate those. I had my right hand over my left. Maybe WASD - JKL?
The dash was not intuitive to use. I spent 15 minutes trying to cross the first gap wondering how the heck do I cross it when my dash won't get me there. Only to finally realize oh my dash cancels if I'm pressing a button. This wasn't intuitive because it would dash for a short while before turning off if I was holding a direction. You could possibly mitigate this if you wanted to keep the dash going for a while. Instead of tap and go forever you have two. Tap, and it goes the set amount you have currently OR if it's holding and you go over that set time you do the dash till the dash button is let go. Shadow abilities and explosion abilities were cool, but were still kinda clunky. Especially with trying to handle a room of AI.
I would go back and work on a more responsive and intuitive character controller before expanding. Art and music are great and intriguing keep doing that! There's some cool environmental story elements going on!
Keep going!