A clever little idea! Had fun with this one. The art style is REALLY well done.
As others have mentioned, a tutorial would be nice. Took me a bit to figure out what I was doing. Managed to get 3 points (and found the 2nd key!)
You have so many subtle polish elements and it feels really good. The particles on walking. The spatial audio once you get the green liquid. Some really nice juice in there.
Overall a solid entry. Great job!