Tried the game for a bit and I completely agreed with other feedbacks about timing inputs. Felt too punishing for me especially on boss fights. Some of the attacks' timing always throws me off and requires insane input response. I personally don't have this issue in terms of hardware but we know that hardware input delay also contributes to this factor especially if people using something like wireless dongle or bluetooth keyboard/controller so would be glad to adjust the timings in the future.
Some minor issues are on the UI aspect such as Options button didn't do a color change when hovering through the mouse anymore after clicking it and go back to the menu. This is specifically on the browser based game not sure on the build. Then on the mastery tab, somehow it jumped straight into the second 10% attack unlock available (?) And the yellow bar from the mastery balance does not light up to the first Health upgrade. Another thing is the button indicator on the UI buttons. I would say make it adaptive to different types of input. Since the game supports controller and MnK, MnK should not have button indicator such as huge spacebar and escape icon. It should only show it to controller player and no need on MnK in my opinion except during the gameplay scene on parry and attack. Or just adjust the size of the icon button.
Another minor issue for me is that you should add a simple indicator tutorial for advancing the stages. For the first time, it felt confusing on which one to choose from. It would be better to show some kind of short description per each icon stages.
Overall, It's a great game to play with. I love the pixel art style of the game. Looking forward for future updates on it! :D