Sloping Passages

[YHWH]

Dwarves can detect them, and I think that's all LL says about them.

I know that Gygax & friends would use them to muddle the map, trick the party and lure them deeper into the dungeon than they realized they were.

But I'm not sure I grasp how to use them as a DM:

1. Wouldn't a gradually sloping passage have to be hundreds of feet long to move just 10 - 20 feet up or down?

2. Wouldn't a slope have to be extremely gradual for a human not to detect it? How much is believable?

[Mark]

For well carved passages in full light, it would take a fair a distance for the drop not to be discernible depending on the slope if you can see everything. When the lighting conditions are weak, it would be harder to detect the drop from sight alone. If the drop is not abrupt, I'm not sure internally it would be easy to detect it without the aid of visual references. In caverns with rough floors and debris, the drop would be even less detectable considering you would always being moving up and down with each step to negotiate the cavern.

[bathwizard]

Depends on how rough the floor and ceiling are. If they are polished smooth, spilling some water or oil can reveal the slope, or your characters may notice the difference in effort walking up and down the slope. Noticing the angle of the feet when standing upright doesn't seem particularly reliable for gradual slopes. If your floor is cobblestones or rough-hewn from the rock, and with no natural horizon as a point of reference, it could be quite tricky to detect a 1 in 20 or 1 in 15 slope. But yes, it would be hundreds of feet long to go down the 30' depth to the next level, Just my 2cp,

[Lord Kilgore]

As noted, lighting can make a big difference. Remember that, normally, characters will only be able to see 30' ahead and 30' behind (the light radius of a torch) so it will be much more difficult to pick up on sloping passages visually.

[bighara]

A sloping passage doesn't have to drop (or rise) a whole level's worth to let the GM have fun with the PCs.

Even a gradual slope can allow a boulder trap to get rolling and pick up speed. Or a change of even a few feet might hide some feature of the dungeon from 2D thinkers. Maybe it can give some kobolds a "pocket" for some low tunnels in the floor/ceiling that the map wouldn't easily show.

re: dwarfs. I usually allow them to "detect" a net ascent or descent in winding tunnels. Sometimes a natural tunnel might climb and fall over a long distance and your depth compared to where you started is by no means clear.

[Irda Ranger]

I was never clear on sloping passages either. I can "detect" a slope that's pretty gradual, and if there was any doubt you could rig a plumb line with any weight and a bit of string. A gold coin would do. Any passage with a slope so gradual that neither of these methods could detect it with certainty would have to travel very, very far to move any appreciable vertical distance.

A more useful skill I often attribute to Dwarves is the ability to know how far they have moved up or down. I (personally) can detect a sloping passage but perhaps only a Dwarf could say with certainty "We are 15' 4" lower than at the beginning of this passage."