The Lost Ability Checks of Caverns of Thracia
Thracia, the much praised dungeon by Jennell Jaquays, gave me and my group a great time over a dozen or so sessions.
And something that always struck me is the variety of attribute checks. Well before the days of d20 + modifier, Jennel was calling for the now well known roll of d20 under the appropriate stat. But she wasn't so set on just that procedure. Now, some of these are probably not going to take off at this point, but I find it fun to twist and use ability scores in all sorts of ways while playing. So let's take a look at some classic examples!
Examples
Strength Checks
1-17: Rusty bars that can be bent on a d20 roll under Strength - 10. Pretty standard stuff. Confer the % chance to bend bars in AD&D.
2-32: Breaking out of a web in a number of rounds equal to 19 - Strength score. Confer in B/X that breaking out of a web is divided into just three speeds: normal human strength, magically augmented strength, and giant strength. That works well for something equally likely to be used on enemies or players, but you may as well reference the score directly if only players are likely to be caught in it.
2-36: "A character with below average strength (or less) will be unable to climb out of the hole unaided by rope or friends." I'm not quite sure what the cutoff is here (maybe 9?), but I like the completely non-random, binary take. You either have the strength or you don't!
2-37: "Danaus' armor is not magic but it will fit any character of 13 - 16 Strength and 5' 6" to 5' 9" tall." This one isn't even a check! Just a note that some characters may be too small or too swole to fit into this dude's armor.
2-40H: In this room, a magically shutting door can only be held open, and just for 1-2 rounds, if and only if the character trying to hold it has 18 or higher strength. Not likely to come up outside of magic, but hey, a cool bonus for the super strong.
2-40I: As above, but for this one the character needs 18(00) strength and then only has a 15% chance to hold the door. Not likely to come up, but at the very least gives the DM a good concept for what kind of strength is necessary (i.e., the strongest a man could possibly be is still unlikely to succeed. But a giant?)
2-43: "A percentage roll of 90%+ by a character of 18 (00) Strength can force it open though." Okay, now we're getting a little ridiculous. How many 18 (00) characters were in Jennel's games?
2-45A: Another suit of armor sized by height and Strength score, although this one is lower (11 to 14). I like throwing in a snazzy suit of armor just for the characters with bad stats, to be honest.
2-46: A "saving throw" of rolling under Strength - 4 on a d20 will avoid getting stuck in the web. On a failure, maybe you're stuck, or maybe you can reference the web rules that showed up earlier! Curiously, it includes a note for using extraordinary Strength with roll under, "Treat each level of extraordinary strength as a seperate [sic] strength point."
Dexterity Checks
I'll spare the details, and point out that simple roll under Dexterity checks (maybe with a small penalty) are used quite often for not falling. These include walking through slippery guano, sidling along the side of a cave river, not falling off a rope bridge as a swarm of bats fills the air, and interestingly, to avoid a simple pit trap.
The most fun one however, is for how long it takes to reassemble a huge automatic crossbow: "it will take the averaged Dexterity of all characters doing the assembling subtracted from 20 in melee rounds to put the thing in working order and capable of firing on the next melee round." The module does not say how many people are even required to assemble it, so I'd have to go with either 2 or 3 so that the character with the highest Dexterity doesn't just do it themselves. Note, this is to reassemble the crossbow and use it when needed. It's a whole other process putting it together the first time, but we'll have to wait until Intelligence for that.
Constitution Checks
Amusingly, in 1-22 we get a roll under Constitution check referred to as a "save vs. nausea" to not lose d6 Strength when confronted with a horrible smell.
Other than that, we have consistent use of Constitution for determining how long magical sleep and paralysis lasts (20 - Constitution score). I'm not sure if there's a precedent for this in something earlier, but it's a nice rule of thumb. At least in B/X sleep and paralysis are given at times for lasting 2d4 or 4d4 turns. This may last even longer, averaging ~10 turns (though much less for more heroically statted characters).
And oddly enough, we get a bonus to a saving throw vs. poison equal to the character's roll equal to half their Constitution score. Perhaps a bit clunky, but a decent way of incorporating both the saving throw value and the character's Constitution.
Intelligence Checks
Caverns of Thracia includes a whole subsystem for using an interpreter to communicate in another language with certain characters who only speak Ancient Thracian. Although, this uses the intelligence of the interpreter, not the PCs themselves. But it could easily be used for when PCs only know a bit of a language they need to communicate in. The interpreter simply has a static modifier equal to 14 - Intelligence (lower, even negative scores are good here) and add that to a d20 roll, ranging from "Correct Interpretation, message clear" to "Message comes across as an insult." to Total message is incomprehensible, nothing understood."
Remember that automatic crossbow from earlier? Well you bet Intelligence factors into figuring that thing out. A fighting-man (and seemingly only fighting-men, as they are the most familiar with crossbows) has "a percentage chance equal to his Intelligence score -10 x 5" to figure out the assembly, and the assembly itself will take a number of hours equal to 25 - Intelligence to complete. I like a special item that needs special attribute test rules just to even use it. Not to mention, it'll be a nice reward for playing off type and having a smarty-pants fighter.
Wisdom Checks
Not much love for Wisdom in Thracia, but evil clerics of Thanatos will have an easier time controlling their undead horde with a high Wisdom. Powerful undead controlled by a cleric need to roll over the cleric's Wisdom + 2 to break free. A simple inversion of the stats is a slick solution in the right circumstance.
Charisma Checks
Not a single Charisma check in Thracia!
Thoughts
Obviously some of these are clunky, but something does speak to me. In particular, I like how resolution for different attributes feels different here. Dexterity is almost always roll under. The test itself, roll high or roll low, feels like balancing on a tight rope. Strength on the other hand is consistent. A character needs this much, otherwise it's a no-go. Either that, or only the super strong even have a chance. Constitution is rarely even a check, rather providing a time buffer or a bonus to other checks. And of Course Intelligence, instead of being checked (shouldn't we be rewarding player skill anyway?) can be used for more abstract things that a DM and player couldn't talk through, and can be used to determine how long something takes instead of if the character succeeds in the first place.
Are these good enough to be "core" rules in the rulebook? Probably not, but part of the fun of OSR style games for me is the ability to take on a procedure or ruling, use it for a couple of one off situations, and then discard for the time being. These rulings are spices to be sprinkled liberally over a nice meaty core set of rules.