The title screen and opening text rocks, as does the general vibe! North's design and animation rules and the sound design is quite nice. We stan a fixed jump arc and the slow movement isn't the worst ( and is interesting! ), but I'll echo the sentiment that one false move is quite punishing. And I'm not sure what function the health provides when everything send you back to the bell anyway.
Some potential ideas: North is a sturdy friend and moves as such, but when it lands it slides a bit, often into the water. Just sticking the landing would really help, it sometimes feels like you successfully judged the fixed jump arc, but then you slide into a reset. I feel like enemy projectiles should just chip away at you, and this would give you more opportunities to get good at blocking. Dealing with the failure of missing a jump is a little more tricky, I don't necessarily have a great solution. Maybe just speeding up the overall player movement would be enough.
I got the attack upgrade and explored quite a bit, but it's late for me and I need a pause. Will revisit tomorrow. But I really hope you continue working on this project, I think it has a ton of potential, cheers!