"SAVING VS. ABILITIES (OPTIONAL): The DM may want to base a character's chance of doing something on his or her ability ratings (Strength, etc.). The player must roll the ability rating or less on a d20. The DM may give a bonus or penalty to the roll, depending on the difficulty of the action (-4 for a simple task, +4 for a difficult one, etc.). It is suggested that a roll of 1 always succeed and a roll of 20 always fail."
- From the 1981 D&D Expert Set, page X51
A simple enough rule, and one that I've used on many occasions running B/X; it is the basis for the BECMI skills first presented in the various Mystara "gazetteers" and later in the Rules Cyclopedia.
[these, by the way, worked pretty much the same as the AD&D "non-weapon proficiencies" (first presented in Oriental Adventures, a book mainly written by the same guy: Zeb Cook), and exactly the same as Cook's 2nd Edition AD&D non-weapon proficiencies...all of which I hate, by the way]
I never much cared for the BECMI skills (even when I liked BECMI), and these days I'm not even a fan of the "roll under ability" rule. Simple as it is, when I look back on the way I've used it in the past, I find myself shuddering a bit.
Why? Because I used it as a catchall guideline rule for determining whether or not a PC could execute a particular plan or out-of-the-box action effectively, rather than presuming character competence. It's an antithetical approach to my current philosophy of D&D play.
But aside from any "philosophical" issues, as a form of micro-managing character action it leads to a higher rate of character incompetence, which is less fun for everyone involved. Consider one of the classic challenges of AD&D: the suspended disks acting as a "trail" over boiling mud from White Plume Mountain. A standard method of getting across the cavern (for those who aren't able to fly) is to make a series of jumps from disk-to-disk, using a "roll-under-ability" for success. Certainly, that's what I've always done in the past.
Here's the problem: with a check of this type, a series of task rolls reduces one's chance of success exponentially. Consider the guy with a DEX of 16...an 80% chance to make the jump to a disk is pretty good, right? Sure...but having to make all nine jumps (there are nine disks in the cavern) means that the cumulative chance of success is only 13%. It's a bit better if (like me) your DM allowed a "reroll" attempt on a miss (a second DEX check to see if the PC can "catch herself") but even then it's no better than a 4-in-6 chance of overall success...and less if the guy has to roll to make it from the last disk to the opposite ledge (a 10th jump). And THAT for a PC with DEX 16...what about the shlub who only has DEX 10?
|"Aiieeee! It burns! It burns!"|
Of course, there's more to complain about than just this. Binary (yes/no, success/fail) systems lack any kind of grey-area gradient. There's no room for partial success (nor partial failure), which can curb the irritation at "whiffing completely" while still preserving the old school integrity of character's NOT always failing up just because they're (story) "protagonists."
Thus enter Steve C's rather brilliant idea of repurposing the standard B/X reaction table to account for more than simply whether or not a wandering subterranean denizen wants to take your head as a trophy for its mate. Steve's idea was to use the table to expedite all manner of random issues that might come up in game, rather than spend time searching for obscure systems or hemming-&-hawing over how to rule certain situations...things that other DM's might determine with a simple coin flip (the ultimate binary test) could instead have a non-binary gradient to it.
For folks unfamiliar with the reaction table, it's a 2D6 roll which can be modified by a CHA adjustment (max of +/- two, and usually no more than one point) or circumstance (again, usually by no more than a point or two). The table results break down like this:
2 or less: Immediate attack
3 to 5: Hostile reaction
6 to 8: Uncertain, confusion (roll again)
9 to 11: No attack, leaves or considers offer
12: Enthusiastic friendship
[I realize that this table originally appeared in Might & Magic (OD&D), but Steve's use of an ability score adjustment is what leads me to presume he's taking it from B/X, seeing as how neither OD&D nor Holmes offered specific ability-based (CHA) adjustment to reaction checks...and Moldvay did]
Steve runs with this, giving a simple five-result table ranging from "catastrophically bad" to "extremely good" as a way of judging all those little things that crop up in a game. I say, hell, let's take it a step further and use it to resolve all those "ability saves" in a non-binary fashion!
Take the White Plume Mountain example. Rather than force players to make a series of jumping rolls, why not have them make a single roll (modified by DEX) to see how well they navigate the challenge?
2D6 (modified by DEX initiative adjustment):
2 or less: mistimes jump, plummets into mud (take damage from fall and boiling mud, as usual)
3 to 5: nearly slips but manages to grasp edge of disk though being completely dowsed by muddy geyser (take damage and al further checks to navigate disks are made at -2 penalty).
6 to 8: holds up on disk just in time as a geyser blows (take moderate damage; roll again to continue with cumulative +1 bonus)
9 to 11: made it across! only light damage taken from geyser splatters
12 or more: what a show! made it across without being splashed (and damaged) by boiling mud.
Nice, huh? So much simpler and quicker to resolve than a series of tests, and with an easy range of possible outcomes. Using the reaction table as a base, many "ability challenges" can be resolved in this way, with tastier results than binary systems, and little-to-no need for any kit-bashed skills system.
Some folks may object to such a simplified system of task resolution, saying it doesn't take into account character experience...shouldn't a 6th level character (for example) be better at such a task than a 3rd level character? To those folks I say: HUH? What in a character's class training has taught her how to navigate some mad wizard's bizarre challenge? Why would "experience" count for any such thing?
This isn't a "skill" in which a character trains (like fighting and thieving and spell-casting)...nor is it something that falls into a character's presumed sphere of competence (like knowing how to build a fire or how to tie a good knot or how to mend her basic equipment). We're talking about strange situations, outside the ordinary things encountered...things where the "save versus ability" roll has (in the past) been the main explicit option. Even if a character HAS done the "jumping disk" thing in a past adventure, chances are she hasn't been prepping every weekend since, like some fitness nut training for the American Ninja Warrior competition.
No...success or failure at these kinds of challenges need a system that shows the virtual crapshoot of attempting it (i.e. via random roll), possibly modified by native talent, possibly modified by other DM-arbitrated adjustments (as with reaction rolls). And in such cases, I think it's fair to have a range of possible consequences, only the worst of which is "abject failure."
This is something I'll be throwing into my future games...assuming I ever get back to the gaming table. Thanks for this, Steve!