People seemed to enjoy my D&D free fall game so I thought I'd share what I did last Monday. I was inspired after playing some God of War on the PSP to see if I could recreate a classic light/mirror puzzle in D&D. Obviously I could just have them find mirrors and place them in key locations to direct an imaginary beam of light. I wanted to use real mirrors and an actual beam of light though. I ended up getting a laser pointer and some little 1"x1" mirrors.
The laser pointer I just grabbed at an office store and the mirrors came from my local craft store. I cut up some popsicle sticks and used them as basses for the mirrors. Next I set up my dungeon using Dwarven Forge Dungeon Tiles but you could just as easily use a hand drawn map. In fact that would probably be easier. I did not account for the unevenness of the tiles. This made it tricky at times to line up the mirrors. I started off by arranging all the mirrors myself and making sure that it was physically possible to redirect the beam through the map and hit all the key locations.
Once I had made sure it worked I removed some of the mirrors. These ones would need to be discovered with perception checks. I also placed some of them in side rooms. The party would need to kill all the monsters in these rooms to retrieve the mirror.
I decided to use the laser in three different ways. First, directing the laser onto doors marked with a special magic sigil would cause the doors to open.
Second, certain large enemies had magic shields around them and these guys could not be hurt until the shield was deactivated by striking them with the laser.
Finally the laser itself would act as a hinderance by dealing damage to any PC that got in its way. PC's could use their move action to move with a mirror, however they could only move half their speed. Then it was a standard action to turn the mirror.
As usual, once the players got involved some of my plans had to change. Rather than leave the laser on and try to navigate around it, they kept sending some one back to shift the first mirror in the sequence. This essentially killed the idea of the laser as a hazard. In hindsight I should have locked the mirrors in place or just had some unseen monsters jump the player they sent back alone.
Overall they really seemed to enjoy the game and I think the mirror puzzle was a hit.