A group of us have been discussing underground environments over at the Adept Play Discord server, and some interesting insights and questions have been raised. We arrived at a critical mass of comments where it seemed prudent to move the discussion over to this site for the sake of deepening (pun intended) the discussion, widening the audience, and preserving the ideas for posterity.
Some of my personal interest in the topic stems from childhood experiences and from a recent film. When I was young, I had a Boy Scout leader with an interest in cave exploration. This led to a number of memorable weekend outings where he took us into some “wild caves”--these are caves which are generally not known or accessible to the public, and they have not necessarily been thoroughly mapped. I doubt such trips would be permitted by the Boy Scouts today. Those caves had some tight crawl spaces, and I remember distinctly times when I was aware that the oxygen level was decreasing as a trail of us slithered through the tunnels. I also remember the experience of deep darkness and of being in situations where the only thing I could see were nearby walls of the crawl space and the boots of the comrade in front of me.
Recently, I watched the horror film Descent, which is about a group of women who go into an unexplored cave. The passageway they are using collapses behind them, and they are then trying to find an alternate exit. Along the way, they discover that the cave is occupied by some violent and vicious humanoids. The film is terrific in giving you a sense of how scary and unnerving an underground environment can be, and viewing it will enrich your gaming experience if you are inclined towards adventures into caves and dungeons.
Tight underground places pose strict limits on three basic human needs: the need for space, the need for light, and the need for air. In a cave, you cannot walk anywhere you want, because the stone walls constrain the space. Light is obviously a precious resource in the environment. And, depending on ventilation, area, size of party, light sources, elapsed time etc., you are likely to find the air supply getting used up.
When it comes to roleplaying games that have made underground exploration a prominent focus, the limitations on space have been embraced. One of the factors that has made dungeons so popular is that they can usefully curtail the choices of the adventurers, at least when it comes to where they are able to go. Of course, they could decide not to go down there in the first place,, but if they decide to enter the dungeon, they are accepting the fact that they will need to follow the corridors and tunnels laid before them. This obviously has advantages for the GM or writer who is creating the adventure since it allows them to control the number of areas they have to prepare in advance.
The need for light in the underground is obvious, but the roleplaying games are mixed when it comes to addressing the issue. Some characters might have special vision, though even superior night vision is useless in a cave or dungeon unless there is some dim source of light. They outfit wizards and clerics with light spells, and some artifacts or treasures might glow. They also encourage players to consider items like torches for supplies, even though some of these light sources would be ill-advised in the actual environment due both to smoke and to oxygen demands.
As far as I know, the topic of air supply in the underground is seldom if ever addressed in games.
To what extent should roleplaying games concern themselves with lighting and oxygen needs in the underground, and how might those concerns best be addressed?
In our chat on Discord, one sage designer clarified the issue for me when he talked about increasing the fun and excitement at the table. As he puts it, “is there something in the rules that will allow players to engage with the problem in a creative way or that will create consequences or contingency beyond slowing down the process of still getting through the caverns?”
To make this concrete, a GM could lean heavily into rules requiring a careful monitoring of light sources. This would involve keeping track of time, maintaining an inventory of torches, left, etc. You might also stress the importance of having someone around to hold and maintain the light source. But if this simply becomes an effort in bookkeeping and logistics, with no satisfying payoff in play, we’re inclined to avoid those rules.
So what I would propose is identifying specific ways that GMs and/or game designers might bring some of these limitations of the underground environment into play, and doing so in ways that contribute to a more satisfying game at the table. I’ll place a few ideas here and encourage others to add to the list and the conversations.
More mystery and strangeness:
Considering how walls and corners block light (not to mention the limited light range of a lantern) can heighten the danger and general wierdness of a place like a cave. A participant at Discord pointed out that online virtual tabletops have brought this dimension into focus for him with their ability to show only selected small areas of a map to the players. In the darkness, other senses take on a heightened importance, so the more careful attention to sound, smell, and touch would activate sensory realms that aren’t always featured at the table.
Countdown clocks with teeth:
I’d consider coming up with an efficient mechanic that would keep track of diminishing oxygen supply in a tight, enclosed underground space (I’m not aware of any game that already has such a mechanic). Such factors as activity level, size of party, number and type of light sources, etc. would play a factor. Much of this would be player-facing so that the players would be generally aware of the limited time at their disposal. This could lead to a dramatic scenario with players making decisions (like dousing light sources or separating to more efficiently canvas an area) to conserve oxygen.
New uses for old tools:
One of the pleasures of roleplaying games is putting characters into challenging situations demanding inventiveness and resourcefulness, and a low-light, low-oxygen environment provides rich opportunities if handled correctly. Would a fireball spell be useful in a low-oxygen environment? Maybe not. Or maybe it becomes refashioned. You cast it into the room and if fizzles, doing negligible fire damage. But it effectively uses up the remaining oxygen in that area, and then you immediately step outside and seal the door. What are those giants now going to do without air to breathe? Maybe the players can come up with new, imaginative ways to open up air ducts or to bring ventilation into an area where you need more oxygen, or maybe they can improvise some apparatus or maneuver to deal with the situation.
A focus on these facets of the underground environment is bound to be more satisfying and interesting if the players have some sense of what they are getting into in advance. A goal here is to see players interacting with the rules and resources of the game in interesting and original ways, considering how they might consider alternate and functional uses for the spells and tools they have at their disposal. It’s hard to achieve the goal if they are cast into a low-light and/or low-oxygen environment without any warning or consideration.