The Secret of the Laser!
Background: In a recent "He-Man vs. Cthulhu" D&D game I ran last month at GameHole Con, one of the puzzles I used in the Dungeons under Greyskull was a laser-based puzzle. The players had to find mirrors scattered around the dungeon to bounce around a laser beam from the beginning of the dungeon to hit various "activation crystals" and open the magically-sealed doors along the way.
So the components for such a puzzle are fairly obvious. First, you need a good laser pointer. Well, it doesn't have to be great, but it needs to have an ON/OFF switch rather than button, so it stays on without having to hold it. We're talking a <$20 one from Amazon is what I use.
Second, you need mirrors to bounce the laser. I bought a bag of super-cheap 3/4" x 3/4" mirrored mosaic tiles for this. I glued one perpendicular to another so I'd have easy little stand-up mirrors. I hot-glued them like that because that way I new that they'd stand up straight, because the front and back of the mirror tiles were perfectly flat. Plus they're so cheap you can make like 10 extras in case one breaks during the game.
Side-Note for the Electronics-Savvy: I considered that with a small breadboard and some Sparkfun-type tinkering you could probably build a little wire with a light-sensing diode at the end that could set off an alarm noise or something simple when a laser hits it. I considered this, but then didn't want to take time to make it and then have to carefully transport it to the 'Con and not have it not work right or something. But it is something to consider for a home game.
Of course, Dry Ice helps make all miniature terrain and laser puzzles pop, but that's a separate post already.
In my game, the players would activate a secret that would release the laser beam, but it would just shoot out of a room and into the hallway, seemingly going nowhere. They'd then have to explore deeper into the dungeon and find the magic mirrors to bring back and bounce the laser forward to strike the red gems and open the doors. Sounds simple, right?
|Dry Ice is optional but really makes the laser shine.|
After getting everything ready for this puzzle I ran into The Major Setback with lasers before I could get it to work. There is one major difficulty with using lasers and mirrors on a bunch of Dwarven Forge Dungeon Tiles (or any gaming table terrain, really) that will mess up your efforts for an awesome puzzle. See, even though the bottoms of the mirrors are perfectly flat, your terrain or gaming table isn't (and some of your mirrors may not be glued perfectly straight up). When you're first setting up a mirror bounce-map for the laser puzzle you might be doing it on your perfectly flat table without the dungeon mat or terrain, it may seem like it works pretty well. But once you set them on the actual dungeon floor the angle of the mirror-bounce changes a little, and each small change in bounce-angle can totally throw your laser accuracy out of whack.
Fortunately, like with all things I complained to Mrs. Chainsword about it, and she saved the day by nonchalantly giving me the answer to my problem I would have never have considered. Though now it seems so obvious to me, at the time I was too caught up in diodes and mirrors to think of it.
So what is the key to unlocking the Secret of the Laser? ...
|Absolutely essential to any high-tech laser-based puzzle.|
I couldn't believe it either, but it works absolutely perfectly. See, you ball up a small amount of silly putty and place it under each mirror. You can't see it when its sitting there, but it allows you or the players to rotate the mirror's angle in all directions (x, y and z) instead of just turning it left/right. This way if the previous mirror gave the laser a bit of an upward or downward angle, you can correct it without having to go all the way back to the first mirror and correct the beam at each and every mirror. Plus it holds the mirror in place on the dungeon floor so it's not disturbed by minor table bumps and the like. It really turns the fairly frustrating ordeal of calculating geometries back into the fun puzzle its supposed to be.
Since then, I've found Silly Putty to be a fantastic tool to have in my DMs kit behind the screen for any strange mini-related request that comes up during the game. Oh, your character wants to climb up the side of that building but only made it half-way? Lets stick the mini's base to the wall with some Silly Putty. Oh, you want to ride your freshly-summoned zombie tyrannosaurus into battle, but the back is too rounded for your mini to sit on top? Silly Putty to the rescue!
|...well this was a hell of a game.|
Laser on, fellow gamers!