This takes me back to my days hanging out on Scratch, which was my first glimpse into game design. As much as I love Gravity Falls, personally I would have preferred to see what kind of original characters you could have come up with. It's a pretty solid platformer in terms of level design and mechanics, but it's missing a few key bits of polish and communication with the player. It would have been nice if there were more sound effects for things like jumping and taking damage, as well as a visual/audial warning for when the gravity flips. For a solo dev though, it's quite impressive!