The Cloudie bug appeared again, where the light is ineffective despite light still being visible.
Only after I closed out of the game completely, did the bug disappear.

Good news — I found the bug!
The light’s shape radius was actually persisting between runs, so when the enemy appeared the game said: “oh, the light radius is already small enough, time to deactivate the light.”
This also meant that every time you lost while the radius was reduced, the next run started with an even smaller light radius — giving you a smaller area of effect without realizing it.
Thank you for spotting this! Your feedback helped uncover a pretty sneaky bug.
I will release a patch update with this and the other bug solved.