ooooh, platformer! That's interesting! (Speaking as someone who isn't always great about stepping outside his creative comfort zone, such as it is.)
I did hit a bug while in the Tomb of the King, while trying to reach the secret that's visible from the entrance: I must have landed weirdly or moved too quickly, and now my frog is shapeshifting. When I stand still it cycles through sign, diamond, fire, nothing; when I move, it cycles through gray disk, blue disk, key, slime; when I jump, it's arrow, and then I think something else but I land before I can tell. (Restarting from the beginning fixes it, though, well, now I'm at the beginning...)