When I see platformers that look way better than mine I get jelly, and right now I'm jelly. I'm going to be repeating some of the comments already here, but:
- can't see tutorial text that's off-screen
- jumping doesn't work properly when hugging walls, and there's really a certain time frame where you can press jump to wall jump, which is annoying
- hitting the mizu character doesn't work reliably - sometimes it will ignore my input, sometimes it will send me in the wrong direction
- mizu characters seem to carry over my momentum (so if I'm moving right, and I press Space + Up, I'll move to top right) which I didn't want a certain points when I had to do chained jumps
- every minute I'll think "am I pressing the wrong button?" and it turns out no, the game just eats my input and does nothing
- when I was playing around with the movement, it was stiff like people said but I thought it was OK if the game was combat based and you didn't want it to be a button spam game. But it turned out to be a platforming game with a few combat elements.
I'd put as much love into the controls as you did to the art if you're building a platformer. This game looks very promising though, good job!