Friday, November 26, 2010

Death Traps

What are the odds of running into a -9 to disarm trap? That's a big question. How come?

The Historical JAGS Approach
As I've said here before, there are some "standards" that JAGS has historically applied to negatives. Let's take a look:

  • -3 is generally "hard."
  • -6 is generally "very, very tough."
  • Negatives to hit targets in combat generally max out around -4 for hand-to-hand or -6 for range. It could be more--but a Level 4 skill (Master Level) removes -6 points of modifier so if you are a (very rare) world-class master and and are targeting things that are -10 to be hit (for environmental modifiers like range and speed and size and visibility) you are taking some monstrously hard shots.
Under this framework a trap that's at -9 to disarm would be, well, pretty damn rare.

However ...
We think that in a dungeon, as per our current Post-Apocalyptic Have-Not dungeon game, a trap that's at -8 to -10 to disarm might be the case in around 5% of the traps encountered.  What the heck is going on and why do we think that?

The Thinking
So okay: you are the "traps guy" in the party. You start life with L2 Traps on a 14- or 15-. After a dungeon adventure (2 CP worth of experience) you go to 16- because you have a 13 COR. After a second dungeon adventure you pop up to L3 (another 2 CP). If you were less dedicated to begin with that might be three dungeons.

Assuming you were a 50 CP character to begin with and had 10pts of negative Traits and now have an estimated 6 CP worth of experience you are now a 66 CP character. You have spent approximately 6 of those CP on Traps skill. You are now a L3 16- Traps Expert with approximately 10% of your CP invested in being that guy.

First  Note: You Never Get Any Better
While not literally true the point has been made that improving on this state of affairs is quite difficult. You can go to L4 (an extra 10 CP or five dungeons worth of dedication). You might go to 17- for 6 CP (or so). If you can improve your COR you can get another point that way too. These are expensive and, at least for Level 4, implies you are a world-class master instead of just, well, a really good "Traps Guy."

You are pretty darn far into diminishing returns here as well unless your environment is really rocking the traps rules. Like: all traps all the time. You better really enjoy disarming traps.

Second Note: How Hard Might The Traps BE!?
If I am on "level 10" of a JAGS dungeon with a character who has been through "8 Dungeons" and gone up "a level" for each one--that is "a pretty deep level" with a "pretty high level character" am I, what? Running into -18 Traps? -8? -5? If we go with the historical solution then a -8 Trap is pretty extreme. Maybe I'm just running into -5 traps meaning I roll at -2 and therefore make my 16- L3 Traps roll on a 90%-success-rate 14-.

That's so good it's almost pointless to have me roll. It's so pointless it's probably boring. 

If this is, indeed, the case then L3 16- as the "top level" is pretty reasonable and it assumes that disarming traps at <10% of your character (by the time the guy has done eight to ten dungeons he's got maybe +20 CP?) basically just means that unless it's some kind of uber-trap you cut right through it without much difficulty and the drama comes from somewhere else.

This is "okay" and there's a reason it's the historical model.

However ...
However, we don't want that for a MMO-style Tactical dungeon adventure. For that we want a complex cross-fire of interlocking modifiers, challenges, and arms-race-style character designs. We want there to be stuff in "the dungeon" that is "challenging and dangerous" even at the traps level ... maybe especially there. So that gives us the Dungeon Challenge Framework.

The Dungeon Challenge Framework
We make the assumption that (a) a dungeon is definitionally a high-stress environment and (b) there will be some degree of 'randomness' in the challenges (they will not be carefully coded to the character's abilities. If you do make that L4 Traps guy you will, in fact, deserve a big edge rather than having the dungeon reconfigure itself to maintain the challenge level: you paid to be good and you are good).

Here's what it looks like: there's a table of randomized modifiers with about 5-8% being extreme (-8 to -10 or more) and many in the -1 to -4 range (the exact proportions are under discussion). The GM (Eric, in this case) also has categories of trap from very deadly to less so and randomly matches them and then assigns them in order to trapped doors (he's randomly creating dungeon levels using some kind of generator).

So you can run into a trap that's at -6 to detect and -9 to disarm and explodes for 30 IMP damage. And we did. It wasn't remotely fair--but that's how the dice fall.

We like this. For one thing, a L3 character reduces the -9 to a -6 (meaning it's a 10- 50% roll) so if you are L3 that'll help a lot (if you were L4, you'd reduce the negative to -3 and cut right through it with a 13- success roll). Secondly although 30 IMP X damage would've stomped us, it wouldn't have killed us (most likely) and that creates the kind of high-stress live-or-die situation we're looking for. So this seems workable (even if that example was extreme).

But You Still Don't Get Better
However, that framework has a problem: this was our second dungeon. What do you run into on your 8th? Is it more traps at -9 to disarm? or are the traps at -17 or something? And if so, what do we do about the fact that your skill level and roll still haven't gone up?

Archetype Traits
The current thinking is that you have Archetype Traits ("Thief"?) that give you SP Pools that you use in the dungeon. These pools counteract negatives and can improve successes where valuable for certain types of skills. So if you have 24 AP in Thief and that gives you, let's wildly guess, 24 SPs for the dungeon, you can use it to remove up to -24 points before you have to regroup (note: that is a lot in Thief--so it better be good). 

After spending CP on the skill tops out, the character can pay AP for more and more. The negatives for traps will go up, but not that dramatically. However, you will see more and more high negative traps which would decimate a party without the SPs to burn.

What About Other Skills and Other Scenarios?
Let's assume locked doors work the same way. Is there a Lock-pick Archetype Trait that does the same for Locksmith skill? The answer is pretty much "yes" (although Thief would work for both and probably Stealth and Streetwise too). 

In "normal games" a character will likely run into traps when other people have set them (see the movie Predators where the group runs into Viet Nam style booby-traps on the alien planet--they were set by someone long ago and are not dungeon-style moving wall, spear firining mechanisms). In those cases you are outside the dungeon framework and are back in more classic JAGS where negatives don't regularly spike to -10. 

However, let's take the "Gone in 60 Seconds" game where the PCs are stealing high-end cars in a kind of underground tournament. This could be declared the dungeon framework and you could well run into a car that is at -10 to be stolen fairly easily. We think this model and thinking allows for character Archetypes to grow in a level-based progression but doesn't require it for games where that's not appropriate.


1 comment:

  1. Just a note on the distribution of challenging traps: the -9 to disarm / -6 to detect trap is currently the most difficult trap I have in my list of modifiers. It's also the only one that's reasonably challenging to a L3 16- Trap Guy character:

    The character has a good (13-) chance to detect the trap -- ~85% -- but only a 50/50 chance of disarming it (10-). An attempt to disarm that *fails* doesn't automatically set off the trap (there's a drama -- if the character loses the drama the trap *does* go off).

    My current thinking is that there's at most one of these per dungeon level -- so an 8th level dungeon would have 8 of these (there are, say, about 10-20 traps in a "medium" or 30-something room level).

    In this configuration, you don't usually have modifiers above -9, but the higher incidence of difficult traps makes having an anti-trap SP pool very valuable.

    Does that sound right? Under what circumstances would you eschew adding another -9/-6 Trap and instead go to the fabled -12/-9 trap? When would you include a -15/-12 trap?