Seemed like a good game. Although this is the first game I've seen anywhere, where the "when you get hit and start to flash, you should have temporary invisibility" is done wrong.
I get that when you get hit you lose a life/heart/hp but after that, you should start flashing and that makes you invulnerable for a few seconds, then when the flashing stops you're vulnerable again.
That's how it was like in the original castlevania games. It helped with strategy and is pretty traditional in all other metroidvania type games as well.
Also sometimes when I press up, my character doesn't feel like climbing stairs and just stands there. Wall jump is terrible too. I guess I'm just more used to the old MegaMan Games style of wall jump where the distance of the wall jump is controlled by the direction you press & hold instead of a fixed distance & direction like the one you decided to use...