In my OD&D campaign, all my players are teens... my son and his friends, and some of their friends. The game doesn't always run smoothly, as I've mentioned here before, but it's usually fun. One of the things I've always wanted to do when running a game is to set environmental clues to help the players get into the game... I've tried lighting changes, which don't work all that well for me, since my poor old eyes need bright light to read. I've tried music, which works fairly well, but I never have time to create a playlist, which would be tough anyway, since I never really know for sure where they're going to go. I've also found music can be distracting, since the majority of my players are band kids.
The last two times we play OD&D, though, I got it right. The party was exploring southward from Milburn Hall, their home base, and came to a 300' cliff overlooking what they thought was a forest. They worked their way down the cliff, and about 200 feet down from the top, passed through a glowing green layer in the air that extended as far as they could see, from the cliff outward. As they passed through it, I told them the air temperature when from the mid-70s to the high 90s, and the humidity from the mid 40s to a hundred percent. As the continued downward, they realized the cliff was higher than they'd thought...the three hundred feet got them to the top of the jungle canopy. They were able make it all the way to the floor, though, and I switched on recorded jungle noise I found online: Exotic Deep Jungle Sounds.
The entire time they were in the jungle, a total of about 8 hours between two different sessions, I kept the sounds running. The first time they encountered something large and carnivorous, I turned off the sound... and told them all the jungle noises died away. The creatures don't matter, nor does the battle itself for this discussion, but the sudden silence in the room brought everyone's attention to me! As I've mentioned previously, for this game, we usually have between 9 and 11 teens at the table, and keeping everyone focused isn't always easy. After the battle had ended, I turned the sound back on, quietly at first, then turned it up again. The next time something large and carnivorous appeared, I rolled for surprise, and they were... so I turned off the sound, and we fought the battle.
After that, each time there was a significant encounter, I'd check for surprise, then turn off the noises. If they were surprised, I'd roll the creatures' attacks; if they weren't, I'd give them time to tell me what they were doing. The effect was truly awesome from my side of the table... turning off the sound and then seeing the "oh shit" looks on the players' faces was great!
Whether the encounters harmed them or not, the sound dying away was a wonderful cue for them to be on guard, and I really need to look for other sound-scapes for use in my games! Anyone else have any luck with sounds or any other environmental cues? Let me know!