DC & CR for crossing unstable scree slope

[Haffrung Helleyes]

A few more things:

I've done just what you describe, in real life (crossed recent landslide with pack mules, in the himalayas). I don't think the DC of the balance check would be anywhere near 25. I certainly don't have 15 ranks in balance!

In general, even when something like this is really dangerous, the chance for a single person to succeed would be high. It's still a dangerous day if you take a 5% chance of sliding down a mountain to your doom!

Also, 30' is awfully narrow for the avalanche. I would make it 3 or 4 times as wide, with a much lower (15?) DC. And I concur that it should be a climb check, not a balance check. Climbing is all about balance anyway. So the party should have to make multiple climb checks, at a much lower DC. A rope won't help here, until someone gets across to fasten the rope to something at the other end.

And in the situation you describe, the up slope from the trail should be way more than 20' high. If they are on a trail on a mountainside, the slope above them probably goes for hundreds of feet, and below them it's either straight down or another slope, for hundreds more. If it was only 20' up to the next wide spot, they would have built the trail there in the first place, probably.

A good film to watch if you want to see an example of navigating around a rock slide is the french film Himalaya.

Ken

 

[Haffrung Helleyes]

Oh, and one more thing:

D&D doesn't model this well, but in general, if a trail is bad enough that people are having to make nontrivial climb checks (IE, checks that an unburdened , reasonably fit person can't take 10 on) , it will be impossible for pack mules to cross, especially if they are carrying burdens.

Ken

A few more things:

I've done just what you describe, in real life (crossed recent landslide with pack mules, in the himalayas). I don't think the DC of the balance check would be anywhere near 25. I certainly don't have 15 ranks in balance!

In general, even when something like this is really dangerous, the chance for a single person to succeed would be high. It's still a dangerous day if you take a 5% chance of sliding down a mountain to your doom!

Also, 30' is awfully narrow for the avalanche. I would make it 3 or 4 times as wide, with a much lower (15?) DC. And I concur that it should be a climb check, not a balance check. Climbing is all about balance anyway. So the party should have to make multiple climb checks, at a much lower DC. A rope won't help here, until someone gets across to fasten the rope to something at the other end.

And in the situation you describe, the up slope from the trail should be way more than 20' high. If they are on a trail on a mountainside, the slope above them probably goes for hundreds of feet, and below them it's either straight down or another slope, for hundreds more. If it was only 20' up to the next wide spot, they would have built the trail there in the first place, probably.

A good film to watch if you want to see an example of navigating around a rock slide is the french film Himalaya.

Ken

 

[pressedcat]

Meant a 10ft cut wall with the slope of the mountain above this, as if the road had been excavated into the side of the slope, sort of like
\
..L
....\

Have downscaled cosiderably from my original idea about an avalanche. Now think it will be a part of the 10ft 'cut' wall on one side of the trail that has collapsed, causing a bit of a fall from the undermined slope above and leaving a slope of gradient 22.5 degrees. This would account for the smaller size (and thus reduced difficultly o traversing it).
I've tried to visualise what a cross section parallel to the path would look like, and came out with something like
...._________......................................_______________
../................\......................................./...............\
/....................\........and from above....../....................\

Obviously sloped the other way as well, and the angles not so exagerated as shown, and the middle not so smooth. Sort of suggests a more difficult climb check to get up to the 'flat' then a reduced DC balance and or climb check to get across to the opposite slope.
Therefore, the harder checks will be at the beggining and end, giving the pc's and idea of whether or not they'll be able to get across (and if they do fail their checks enough to fall, they'll be sliding diagonally so, depending on where they start the climb, may end up back on the path.
Had another rethink and this is what i've got currently: below is an overhead view of the scree slope, narrower but steeper edges at top, more flat but much wider towards bottom. I've divided it into 7.5ft (ie one climb check for m critter) blocks, and the number in th paranthesis are the climb DC. If the pc can pass a balance check equal to the climb check's DC, will gain a +2(or more?, opinions please) on the following climb check

......|14|12|10|10|12|14|
......|12|12|10|10|12|12|
....|12|10|10|10|10|10|12|
.|10|10|10|10|10|10|10|10|

If the character fails the climb check by 5 or more, he slips and must pass climb check at DC=10+slope's DC or slide d3x5ft downslope and take d6 non-lethal damage.
If the character wants to climb straight up-slope, must pass a dc14 climb check.

So there it is. Many thanks for all the advice people have given me, as it has hopefully turned what would have been a pointless encounter into a genuine choice for the pcs. All that is left now is to polish off the edges (notably how much bonus a successful balance check should grant to the clib check), and to decide on a challenge rating; leaning to about CR2, possibly CR3.

Question to primitive screwhead: do you mean Legends and Lairs:Wildcraft, a sourcebook of wilderness adventure? as this was the only book i could find on an Amazon uk search
(amazon called it wilscape, but cover said otherwise)

 

[Primitive Screwhead]

Legends and Lairs: Wildscape is the one.. Amazon.com can be twitchy sometimes with thier pictures...

Your idea looks fairly decent, my main concern is that even with a DC 10, at least one of the 6 checks is likely to fail.
How would you handle the climber tie-the-party-together?

Otherwize.. its much too late for me to figure out any problems with it

 

[pressedcat]

Thanks for the link, as that wasn't the book cover that Amazon was showing me (though it looked very similar).
If the characters rope themselves together when crossing, i'd probably rule that if one of them slips, an adjacent pc can roll as normal to catch them (ie catch DC=10+slope's DC) even if there's more than 5ft between them, and without the normal touch attack, and also let up to two other pcs attempt to aid this catch test if they are adjacent to either the person falling or the person making the catch test.
If the pcs string a rope across the slide zone, i'd probably give a +2 circumstantial bonus on all climb tests.
The biggest problem would be getting the donkeys across, as they wouldn't be able to use a rope to aid their climb, and it would be difficult to use a rope to brace the donkey due to it being at a higher level than the people either side on flat ground. Also, anyone care to estimate how much a donkey weighs? I'd guess around 20st (280 Ibs), so probably beyong an average persons max load, so a single person wouldn't be catching a falling donkey. Maybe let a couple of people escort the donkey and make a joint catch attempt. Possibly if someone walking the donkey was to make handle animal attempts to lead the donkey along the safest root, I'd give a +2 circumstance bonus on the donkey's climb test. Any other ideas on this would be welcome.

 

[Primitive Screwhead]

If I had to cross a short pile of scree like this during an excusion in the mountains and *had* to get the donkey's across...

Well, I would already have plenty of rope and some good pitons. I would tie in the rope to the wall on both sides.. with the best climber being the one to venture across first before tying the rope in on the far side..

Then I would manufacture slings for the donkeys... it may require a couple trips and some high 'handle animal' checks, but the rope guide and sling {with a lead-line to drag the donkey across if need be} would get them safely across.

Game mechanics it would require a number of Use Rope checks, most of which you could Take 10 with, a number of climb checks {to tie into the rock face} which you should allow a second check to test the tie-in without risking life or limb { orgrant a +2 to the check instead of doing multiple checks}, then Animal Handling and STR checks to get the donkeys across. As long as the party has enough rope to cut up and use, a small scree field should be relatively easy to by-pass, altho it will take time.
{Take 10 with Use rope costs 5 to 10 minutes per donkey/PC, Climb checks to install tie-in should take 10 minutes per side, each cooperative crossing could take 5 minutes, an uncooperative crossing would take upwards of 15 minutes.}

Intelligent use of blind-folds and seperating the donkeys {so they don't freak out by wathcing thier buddies slip off the path..} would be wise.

All in all you could turn this into a fairly decent non-combat encounter
{See.. I got sleep!}
The hard part for you is being able to stack modifiers for what the party comes up with. Good ideas should have some mechanical contributions but you don't want to turn it into an exercise in math.

 

[pressedcat]

All in all you could turn this into a fairly decent non-combat encounter

Thanks. I'm pretty pleased with the result myself, though i needed a lot of input to get there. I'll probably think carefully before chucking too many more of these encounter types in before i feel more confident as a dm, as its taken a lot of work and begging help from others.

Now i just have to look forward to my first game so the pcs can opt to play safe and go the long way round... :\

As to describing the encounter when the pcs arrive, how should i go about it. Do i give just them a description of what they see, do i give them a few hints as to the difficulty class (ie an average person could make it across the slope on a good day...), or do i tell them what they're aiming to roll? Although i've been playing for several months, i've not really come across any skill encounter that were quite so complicated before and am not entirely sure what is the best way to balance maintaining the senese of immersion without starving the pcs of so much information that they decide to just turn around and go another way.

Sorry if it seems like i'm asking other people to do all the work for me, but the person who normally dms and is far more experienced is off on a 2 month holiday, and so i've got no one to bounce ideas off of or get tips from.

 

[Haffrung Helleyes]

by the way here's a tidbit I learned in Zanskar (Indian Himalayas):

When you have a bunch of pack horses, it's good to have a mule in front. This is because mules are generally less afraid of rope bridges and the like, and will cross them, while horses will not, unless they are following another animal. So, you put the mule in front, and the horses all follow it.

Ken

 

[Primitive Screwhead]

...and so i've got no one to bounce ideas off of or get tips from.

And thats why I wander these boards.. to bounce ideas and get tips from people

 

[Man in the Funny Hat]

Regarding the setting of DC's you were on the right path, as it were, but working improperly from the top down. That is, you were starting with the maximum that you figured a _PC_ would be able to roll for the check. That's the wrong way to go about it. What you need to do is think of what a normal, average person could accomplish - what the MULES could accomplish. What chances does the mule or the mundane, lvl 1 NPC have in crossing this scree slope? THAT'S where you set the base DC. The problem after all is not can the PC's alone get across, but can they somehow safely get the entire pack train across and that has diddly to do with the _PC's_ skills and modifiers and everything to do with animals and NPC's skills and modifiers.

From there you need to look at running the game from BOTH potential paths - the PC's proceed across, or the PC's turn and try and go around the obstacle. The CR then becomes based on how difficult it is to OVERCOME the obstacle - and that means overcoming it by crossing OR by going around it. Either is a perfectly valid solution to the problem/obstacle that the scree slope represents and the CR and associated XP award must be the same either way. It is therefore irrelevant HOW the PC's endeavor to cross the scree. That's THEIR problem - NOT YOURS. Yours is simply to determine A) if it's possible, B) if YOU can think of a reasonable way to do it that you will allow them to succeed with, and C) whether simply going around is comparable in difficulty and that it qualifies as a viable "solution" to the "obstacle".

Whether you PREFER one option over the other must not be a stumbling block to your plans. You MUST be able to handle the game REGARDLESS of what choice they make when you face them with this obstacle. If you really want them to go around - MAKE them go around. Don't even give them a choice about it. When you face them with a "false choice", an obstacle that is so difficult and so dangerous that they really don't have a choice of even attempting it, then it seems like you're railroading them. Once you remove the false choice it seems more like plot development rather than beating them with a stick to make them keep to the rails.