Two 8‘ tall, 1‘ diameter stone posts stand in alcoves along the southwest wall of this room. Each post is encrusted with numerous crystal lenses of various hues. The floor of this room is comprised of 1‘ square white tiles. With the exception of a 2‘ wide path (indistinguishable from the other tiles) that runs along the east & north walls of this chamber, stepping on the tile floor of this room causes beams of rainbow colored lights to shine from the posts, bisecting the room. Many of these lights are harmless, but some display strange properties as determined below. Should the room be crossed by walking anywhere other than the safe path, the Labyrinth Lord should roll 3d6 to determine the results of the rays.
Those struck by the beams are allowed a saving throw vs. wands to avoid the effects, but they must announce that they wish to make a save BEFORE the result of the beam is revealed. It is possible to inadvertently dodge a beneficial beam as well as a harmful one.
*The beam effects are based on getting a pair, straight, or 3 of a kind on the 3d6 and ranged from taking damage, being healed of all damage and afflictions, or gaining a level.
It was rather tense when players were asked to decide ahead of time to make the save or not. Most players chose to save. The room was on the way to an area of the dungeon they were interested in exploring, so they had to deal with the room multiple times. They eventually figured out a way to get past it by throwing flour on the posts and preventing them from emitting light.
What I like about the room is the risk/reward choice and that it requires you either take that choice or figure out an outside the box way of dealing with it.