I'm... not able to replicate the exposition issue, the SOUL layering issue, or the healthbar issue.
due to limitations of the system I'm using I don't know if I can do the "object visible only inside the light" thing.
I can make something on a lower layer, so it's darker outside the light, but unfortunately I only have square/rectangular clipping boxes to work with, not circular ones, as helpful as that would've been for a LOT of things involving light with this fangame.
I can definitely have easy/normal/hard variations for how severe the darkness is, as well has have an option for attacks to have X damage multiplier.
EDIT
I think I might've figured out the exposition thing, did you happen to play my VS susie weird route fight and die over 100 times?
if so, I had a leftover thing in exposition that checked how many times you died, with a 'deaths' variable connected to the cloud.
this one also has a 'deaths' variable connected to the cloud, since the variables share a name, and both connect to the cloud, maybe they're being conflated?
(dying to in the VS Susie weird route fangame caused the exposition dialogue to change at certain thresholds, eventually just stopping at 100, I just- forgot to take that out, in later games since the Noelle/Ralsei one didn't have a death counter)