Great animations and movement! The game feels smooth, and it's nice-looking.
Here's some feedback :)
Player healthbar_2 is coming out to the left side of healthbar_3 when damage is taken.
The obvious one is that the boss doesn't die when his health is depleted to zero. In cases where he is near a wall, his movement makes him clip out of it.
The combo multiplier is always visible. Starting the game and seeing ''0x'' is kind of confusing. It would be nice to be visible and start when 1 or 2 attacks are made.
Going to the bottom or right wall does not fix the camera in such a way that the player's screen is not half void.
I hope I'm being helpful. I can provide pictures if needed. Overall its priety solid for what it is, keep up the good work. :)