The main two issues I have with your game is 1. the clunkyness of the player and 2. the clunkyness of the enemies.
First, and simpler, is the clunkyness of the enemies.
You need to be more consistent in wind-up animations of enemy movements, as they are currently all over the place. The wind-up of the knight is incredibly long and easy to react to (due to his block), whilst the wind-up of the Taurus is too fast to properly react to. Gargoyles have no wind-up to speak off, they just have a spear leave their body at some point. Wind-ups, even in the NES Castlevania's, exist and are of decent length.
This is especially bad with the boss, the werewolf has three different moves that use the exact same wind-up animation and sound cue, but require different methods of evasion. If you're close to the werewolf and he growls, you must either walk away (slash & jump) or jump (dash) to evade his attack. If you're too close, immediately jumping is the only way to evade the dash, but if it turns out that the wind-up was actually for a jump, then you're guaranteed to get hit. Providing different wind-up animations and sounds will help significantly.
Then there's the clunkyness of the player.
Right now, the player feels like an animated sprite that just drags over the floor. You want the action of a player pressing a button to be immediately reflected, and whilst old Castlevania games did this, you do not. Instead, you made a very clean walking animation. You should adjust the startup of the walking animation to have more punch to it. On the first few frames, the character should already have made his first step. See pretty much every NES-era game for reference. Remember, when a player presses a button, something awesome has got to happen!
Many games allow you to modify the momentum the player has mid-jump. Even if this exists to a minimal extent, simply adding this will make the player feel way more in control. Being able to cancel out a small part of your jump momentum to stop yourself from falling down those chandeliers helps a lot.
Small nitpickings:
>Gargoyles are annoying (and I assume intentionally so), but they are too cheap at the moment. You jump higher than you have vision, so it's very easy to jump into a gargoyle you can't see. The only way to dodge it is to know where and when exactly the fuckers spawn. This is worsened if you are standing at the very top of the room, as you are given even less vision.
>The room where you have to jump over two large chandeliers is fucking retarded, and face-tanking combined with intentionally manipulating gargoyle spawns is the only way I can pull it off consistently. This difficulty is way too synthetic.
>There is a small section you can skip by intentionally jumping into a gargoyle and using the vertical knock-back to get up on a platform.
>Knights, when blocking, do not inflict touch damage. You can literally walk through them and ignore them because of that.
>Bats continue to move vertically when the game is paused.
>Because you can't attack whilst crouching, dodging a Taurus by crouching under his attack makes you vulnerable to bats in one section.
>Projectiles continue to exists after they've been off the screen for a while. This may not seem like a big problem, but if you fall down from the chandeliers, you might suddenly find yourself being attacked by gargoyle spears where previously were none.
>No knockback from getting hit whilst standing. If you don't want player knockbacked of ledges, simply code it so that knockbacks cannot throw players off platforms.
>Iframes from getting hit are on the short side. Extending them a tiny amount would help a lot.
>When walking through the edge of the screen and transitioning to the next one, you should let the player character keep walking. Makes the transition more natural.
>Your font is too blurry (but you already know this)
>The large chandeliers in the chandelier section are just the small ones upscaled, pls provide higher quality, they are ugly.
>The Enter key is good for going through some menu's, but not all of them. Some require space instead. Make keys behave consistently.
>No CRT effect on thanks4play screen
>Allowing players to retry just the boss, even if it's just for the demo, would be nice. Having to redo the chandelier section is too much of a pain that I don't want to bother.
Things I want to see:
>Give players a crouch attack
>Give bosses a health bar of some sort
>Some sort of indicator for check-points