Benjamin Olson
Hero
My semi-derived from Out of the Abyss campaign had the "faerzress", residue of ancient Elven High Magic, giving a soft glow to the tops of all the great caverns of the Underdark. Having actual darkness is awesome for when players are exploring particular locations where I have an interesting idea for how to use darkness, but just having it be dark for days on end of travel wasn't my jam and would sacrifice a lot of spectacular scenery for some fussy immersion and general spookiness.