I like your central mechanic a lot, I think it could really flourish if expanded upon. I also like the way it is kind of organically taught at the beginning. The graphics and all are of course a bit wonky but for a three hour game that's completely fine. Plus, you even added sound effects! One thing I do want to mention is that when you're touching the ground, the health should just replenish instantly, otherwise you're just waiting around doing nothing.
That section turned out way too hard and I'm also aware of the hitbox problem. I made the hitbox this big as a last-minute fix to avoid a bug where the blocks didn't kill you, but looking back I should've simply gone without the fix to avoid making the game this frustrating. There will be an updated version soon which will include a proper bugfix, but for now I hope you had some fun playing anyways. :D
