An upcoming challenge in my Planescape game involves the PCs making their way across a near-demolished area of the Infinite Staircase, a series of multiple damaged stone platforms, doors to strange places, with wrecked stairs joining them. In one section, a very long platform is dotted with craters and holes. The craters still burn with a glabrezu's recent rampage, casting light like a torch, whereas the holes are dark and anyone or anything unfortunate enough to fall into them drops to a likely demise.
Perched atop a stairway some 140 feet above the platform (and about 140 feet away from where the PCs might enter) is a manic chaos sorceress. She stands in darkness on a landing, keeping watch for anything coming by with a light source or anyone entering the areas illuminated by the smoldering craters. Anyone she can see is subject to her potent magic, mostly fire-based, including fireballs.
The craters are placed such that they run the length of the platform, with 10 to 15 feet between the areas of light, leaving a path by which someone could cling to the shadows if they wanted to. However, within the darkened areas there may be holes and an almost certain demise for any who fall into them.
So do you try to stealth your way past the sorceress and risk falling? Or do you stick to the light and face her fiery wrath? And if you stick to the shadows, how do you communicate to allies without darkvision in order to guide them safely and still remain stealthy?
It'll be interesting to see what they do.