By dev request, and because this game/demo is awesome, I've continued my gameplay!
The audio in general is some quality work, setting the tones of the areas, especially when the boss music kicks in. And holy carp that jam during Angel's fight. The overall atmosphere for the alien tube room had a nice creepiness to it, accentuated by the goopy bubble noises. I hate organic sounds, but that was a nice touch. And, of course, all of the gameplay was excellent. I like that the enemies are never just one-and-done, so you actually have to fight them or try to dodge around. Angel was a heck of a fight that kept me on my toes the entire time, never predictable, and the other two big fights were nicely done as well. No time for rest against these guys.
Of course, being a demo and early work, it's not without flaws. I notice two in my video, one involving the giant doors you unlock still sort of being there, but invisible, and the other is the energy bar depleting in an odd way sometimes. I also have a slight issue with the Jetpack stopping air combat randomly and at inconvenient times. Have played the game on my own time a little and really got screwed over against Angel when I'd try a combo or dodge and then just...stop.
Can't wait to see this as a completed work though. Smooth out the combat so combos don't feel as jerky and this'll be a really fun hack'n'slasher.