I liked the idea that you were going for Where you beat the first half of the level by collecting the orbs in the normal stage. And then when everything gets red and spooky you go back to the beginning and do it over in the level you decayed.
However, the orb tracker was a little busted. Even though you would restart the level, all the orbs you had previously collected carried over. So it would say 0 but in truth, you had every orb so I didn't have to solve the level as you intended.
The movement speed was agonizingly slow, it made every level feel like a drag and I feel like the concept would have benefitted from faster moving and possibly tying the two jump buttons together instead of having them be separate.
Overall I think the mood and the audio worked great and besides the things I mentioned above it was a nice idea!