the concept is really good, but it needs huuuuge improvements.
things i like:
-the combos: they are freaking crazy for a mobile game!
-the difficulty: it's hard enough, especially the boss
-the style of the game: it's quite original, i like it!
things that needs improvements:
-scenarios: they're too much empty
graphics: need improvements, mostly shadows and ambient light in general
-background: simply there isn't one, just a white background
-controls: sometimes they don't respond, dodge and parry sometimes don't work well
-camera: it passes through walls, so you cannot see anything
p.s: i think the moveset of the boss is too fast, in my opinion the movements needs to be slower to let the player dodge/parry perfectly, and in that case maybe the damage of each attack to be stronger