Fog and Blacklights are no problem, and yes you will reduce visibility. Now fog and strobe lights, that is just disorienting and trippy, I use that effect in one of my "hallways" in my maze.
Yes. I purchased a bunch of these masks which will be suspended from the ceiling on a FCG type mechanism so they move up and down. I'm going to let my kids paint 'blood' on the masks with the deepest red black light paint I can find. I also purchased a bunch of UV reactive eyeballs and those will also be floating in there. I may throw a non-UV reactive spider on the crank too just to bump into people.yeah i use fog & black lights! are you going to have uv reactive props for the black lights?
if you want to reduce visibility, don't reduce it too much ... you don't want any tots getting hurt