I liked the Gura sprite and the voice lines.
The platforming is very hard and requires some very precise moves to get across some sections. Definitely would tone it down a bit, at least in the first levels.
I wish there was a save system. I was planning to come back to the game later to see if I could clear it, but sadly it restarts from level 1. I think I had reached level 5 or 6.
For the controls, I don't know what the I key was for. It only made Gura blow some bubbles. I did all my platforming witn U (jump) and O (dash?)
A couple more things:
1) The game viewport should be a bit smaller since not everyone plays at full screen or has a 4k monitor to fit a full HD web game.
2) I suggest adding to the game description that Gura can double jump and that the trident can be aimed. I didn't figure it out until later. Probably could improve it after the jam by adding some kind of in-game tutorial.