Ah, I found the controls! I just didn't look for them in the right place.
I also think the grappling hook is a cool mechanic! It was just confusing at first because when you first throw it, it looks kind of like a snowball before it sticks. The hook does make it more interesting with the puzzles. Really the biggest thing I found was a bug where sometimes if you jump and throw the pickaxe, you'll keep slowly floating up forever, but that's easily fixed with a restart.
I'll definitely bump the score up now.
But yeah, the colors and cuteness of the character are the strongest parts, in my opinion! Thanks for posting it.