Well, I've been doing a lot of preparation for the upcoming paired Demon: the Fallen sessions whereby an intrepid segment of the Fallen Court in Adelaide are going to delve into a series of tunnels that begin in Nairne and lead under Mount Barker and then north west toward the CBD. As my players are some of my readers, I won't detail everything about these catacombs (a few already know the reasons behind them due to a prior Vampire: the Requiem game I ran earlier, but not all). Suffice it to say that a minor Earthbound has more recently moved in with the remnants of her cult (only 3, or so they suspect, as the other 7 of the 10 that were brought to Adelaide have been kidnapped by the Infernal Court).
This Earthbound is a Malefactor (a demon that can build all kinds of enchanted objects, play with the earth, and warp existing paths) so you can imagine that a warren of tunnels might be a little concerning to them. Not to mention the fact that she has quite a bit of Death and has actually raised a number of zombies to prowl the passageways (at different states of decay, and thus, speed and mobility).
To prep the rather random nature of these tunnels, I created random event cards that I will make the players draw. They pick five cards, I weave it together into something. Don't worry, they're not D&D-style 3 Wombats and a Dire Kangaroo. No, no, they're environmental things like Crawlspace Passageway (low ceiling means you have to crawl) which don't go away until another tunnel-based card is drawn. Or cards on number (and health) of zombies met. Or ammunition finds from previous, lost explorers. Or traps left behind. Or strange noises.
All kinds of things, really. I call it my Dread Deck as it puts some of the onus for the Terrible Things that will happen onto the players who have to draw from it. It puts their fate squarely into their hands (at least on the surface, really it's Lady Luck), which since their picking which tunnels to go down actually kinda fits.
I've also made a point of creating Item Cards for everything they're carrying as this will be a Survival Horror caving adventure so what you see is what you get. If they haven't mentioned it early enough for me to make cards (in a pinch, I will just write the detail on a new one if they argue well enough before entering in) then odds are they won't get it. If they haven't mentioned it before entering the tunnels ... good luck.
I am nice, though. I have sat down with them and reminded them about things like light sources, water, and ammunition. Those with higher Survival have been given more hints.
Oh, I will be remembering their weight limits, too, as mobility is a BIG issue in roughly made tunnels and caves.
Tune in tomorrow for the starting course of How To Run Cave-Based Survival Horror where I'll go over each bit piece-meal with some advice of what worked and what didn't.