Wow, quite the good puzzle game we got here!
For the most part, it feels solid in all aspects: an intriguing core concept of leg durability meaning you need to carefully assess each move, overall pleasant presentation and controls, smooth escalation of difficulty that hooks the player both with great tricks to keep them on their toes (like having to intentionally break themselves when you'd think you should always keep yourself healthy) and tons of new mechanics like grass and bouncepads that are taught to the player very intuitively, and bonus content that serves up additional fun challenges to go for. I was easily hooked!
If I were to have any complaints:
*I felt like the grass, which serves as a soft landing pad, could've been something else a bit more intuitive like snow. Snow would pop out a bit more strongly visibly (the dull green of the grass can easily blend into the dull brown environment) and more easily represent the quality of 'softness'. Would've also loved if landing on grass or snow played a soft sound effect, like a puff, to more accurately declare its use: maybe even have a puff come up visually as well. Bouncepads could also use some sound effects when you use them. But then again, the way you set up the level teaches the grass quite well, so I might be complaining about nothing.
*One big constant and confusing annoyance I had was picking up repair kits mid-jump and having you not have full durability at the end of the jump. Yes, if the repair kit is hanging up in the air and you grab it mid-jump, it makes some sense that landing after the jump will result in your having damaged legs, not full legs. But when there is a repair kit on the ground and you land on top of it from a jump, I feel like that should give you full legs, not damaged legs: so silly to have the very minute gap between grabbing it and landing count as damage.
*Also I found it a little silly that it represents the levels that still have a battery to collect with a pip: usually I feel like common sense would make it so the levels that I have collected the battery in would be the ones that have a pip, not the blank ones, as blank usually represents a neutral state. Also a bit strange that if you beat level 9, but not level 10 yet, the level select will have level 10 as a question mark, when I feel like it should be 10 since you are on it, similar to how the game starts with level 1 as not a question mark because its the one you're on. But whatever, got used to it!
*I did have a few glitches come up, like when I fell onto an elevator platform and instead of landing, it kept me on top of the elevator in a falling state.