## Cubic ST and Double HP – combined

There’s an interesting thread with some strong opinions being given over on the SJG forums working out the details, pros, and cons of a house rule where you double HP (and DR). ST-based damage would be left alone, in order to restrict the muscle-powered weapon damage to penetration values more in line with firearms.

Given the wound probabilities (really, not necessarily that bad with modern medicine unless certain vital bits are hit – you’re going to be messed up but a fairly low probability of dying) the fix for firearms under this system would be to just give them all an armor divisor of (2).

So the general penetration formula remains the same. Wound modifiers would probably have to stack with hit location (so pi+ to the brain is x1.5 x4 = x6, while the vitals x3 and pi+ would be x4.5, rounded up to x5) in order to make up for the loss in low-grade lethality. Does that mean impaling goes from x2 to x4, and cut from x1.5 to x3? Probably not – those stay the way they are.

So, that’s the theory, and the pros and cons and dos and don’ts are pushing 90 posts, so it’s contentious in many ways.

# Double HP and Cubic ST individual concepts

Still, I talked about this before. Rescaling GURPS HP had me musing about the pros and cons of using double the HP score, and its impact on resolution for things like body mass. My parting shot really only noted that the increased resolution that double ST/HP provided was pretty friendly.

However, even right before that, I’d noted that yet another concept, posited by forum user Wavefunction, which was figuring Basic Lift off of the cube of ST, rather than the “quadratic lift” basis of the current Fourth Edition rules (and compared again to the linear ST of the Third Edition and earlier rules).

The “good news” about that was that if you restricted ST to the current equivalent to a ST 20 (Basic Lift 80 lbs), that dropped the Cubic ST equivalent score to ST 16. At that point, you punched at 1d+1 (as much penetration as a .22 LR bullet), and swung for 2d+2 (as much penetration as a 9mm pistol).

Now, one should probably give significant armor multipliers to such blows – at least (0.5) if not (0.33) for fists and such – but at least the upper end didn’t have you swinging for enough penetration to make a 10mm bullet look like a poor trade.

Of course, that’s realism. As I was discussing this sort of thing tangentially with +Christopher R. Rice as I made a Captain America-type superhero at nearly 900 points – the issue with punching folks for a living isn’t that hitting them is more effective than guns. It’s that, in a world of guns, you usually can’t survive closing to fisticuff distance. From that perspective, both bows and fists/feet need the damage boost to make up for the fact that they just suck compared to ye olde .40 S&W. That’s an explicitly genre-balance argument, not a realism one, but nonetheless, the terrain is clear.

# Let’s all eat Reese’s Peanut Butter Cups

What I did not do, and probably should have, is combine the two concepts. Ideally, this would give the increased resolution from doubling HP, the matching of ST and body mass for cubic ST and the cubic base of HP. We’ll need to tweak to get the damage scaling, but that’s tractable.

So, here we go. The Big Chart.

This one is scaled in HP, with the assumption that ST = HP, since my original thought was that you’re basically buying body mass, and then can tweak your ST by up to +4 on the upper end, Why that? We’ll get there.

So let’s look at the table for a bit. The green band is the starting HP for GURPS with no adjustment to how HP are calculated from body mass other than doubling. That is, take the cube root of weight (so 125 lbs –> 5) and multiply by 4. Unliving/Machine and Homogenous/Diffuse (p. B557) would thus be x8 and x16 times the cube root of object weight.

The shift to cubic ST means that (as you can see from the table) the 6xBL threshold and the actual object weight scale well, so a ST 50/HP 50 critter should move in the same manner as a ST 5/HP5 creature. That makes it easier to pick ST and HP values for oddball monsters, I think.

This probably means we can use the Size and Speed/Range Table for a comparison of muscle power to mass (ST to HP) and get pretty good “you can launch that object so far” values, which would make it relatively easy to accommodate ST in the jumping formula, as well as velocities and damages for thrown objects and weapons. Good stuff, and rationalizing all of that in one rule is worthwhile.

Anyway, the green band is the same default basis as the current rules, except HP are doubled. Basic Lift is left at 20 lbs.

Now, when looking at the upper end of the scale, what used to be ST 20 (and Basic Lift of 80 lbs), the scaling change means that that value falls to ST 32 on the new scale,with a Basic Lift of 82 lbs.

This means that unlike the range of 10-16 we got with just Cubic ST with no change in HP, players can easily make finer resolution distinctions in ST scores within the normal range. Given that 6-8xBL is probably a good proxy for world-record bench presses, anywhere from ST 34 to ST 36 represents a human maximum. I’ve previously pegged squats as around 1.5x that value, so 9-10xBL works there, and again, dead-lift and squat of around 800-1,000 lbs tags well there. On the “low” end, it’s not crazy-town to have a 160-lb person pressing 240-lbs, so having HP 22 (166 lbs) be as strong as ST 26 (6xBL of 265 lbs) doesn’t strain credibility.
What about bows? Using the Deadly Spring’s pegging of maximum bow draw as about 2.5xBL, and allowing an extra +4 to ST with leveled Strongbow perks and perhaps another +4 for Arm ST with Special Exercises, our HP 22/ST 22 person could wind up with ST 30 for the purposes of drawing a bow – that would be a 68-lb. basic lift, or a draw weight of 170 lbs. That’s a proper adventuring-strength bow! It’s also on the upper end of the Mary Rose reconstructions, which hit as much as about 185#. Mark Stretton, one of the more famous heavyweight longbow guys (but not the only one) masses a lot more than 165 lbs., and he pulls a 200# bow (he may pull more; I’ve seen the video of the 200# one). I’ve seen a much more svelte guy draw back a 170# bow and make it look easy, so I’m not scared of the results here.

# Whither Damage?

The big question here is what happens to damage? Well, with the forces in pounds, energy for penetration should probably go as the square root of basic lift. That will scale it on the same trajectory as firearms, with is one of the goals of such projects.

Where do we put 1d, though? I don’t have much of a problem with old ST 14 (with 39 lbs basic lift) having a 1d thrust score. If we assume that stays constant with a BL of 39, that means 1d thrust happens for us at ST 25. If swing gives about double the force of thrust, that’s about 40% more damage.

That’s about +3 per 2d (which is messy), but a +1 or +2 per die is less so. Let’s give it +2 per die, which is still about a 40% reduction in both the absolute value of damage as well as cutting down the scaling quite a bit. So: ST 25 is 1d thrust and 1d+2 swing. Note that if you give thrusts with an appropriately-constructed weapon an AD of (2), this results in the thrust being better able to penetrate armor than the swing.

What about default and maximum ST?

ST 20, our new default, clocks in at 2.5 points of damage, which is exactly 1d-1. That’s actually a one-point boost over ST 10 using the table on p. B16. For swing, it should be about 3.9 points, which is between 1d and 1d+1, so the “2 per die” thing is a bit generous, but not horrible, giving 1d-1 for thrust and 1d+1 for swing.

At the upper end with ST 32, scaling as the square root of Basic Lift, we get 5 points of thrust penetration and about 7.9 points for swing. That’s between 1d+2 and 2d-2 for thrust, and about 2d+1 for swing, which means the 1d+1 would be a better fit for thrust.

That very much reduces the range of damage between average and what’s considered the normal human maximum. That’s going to make things cheaper, since the highest proportion of the cost of ST is Striking ST.

# Cost Breakdown

ST is one of the only attributes to break neatly and easily into its component costs. GURPS values striking at 5 pts per level, lifting at 3 points per level, and HP at 2 points each. That means you pay about 10 points per point of thrust damage.
Applying similar scaling to this new scheme, we get:
• HP are straight-forwardly 1 point per HP. Going from ST 20 to ST 32 should be 12 points.
• Striking ST thrust damage goes from 2.5 points to 5 points in the new scaling. That should be 25 points if the cost per point of damage stays the same. We’ll assume that it does, since one of the purposes of the re-scale is to lower the ability to deal penetration.
• Finally, the move from Basic Lift 20 lbs to Basic Lift 80 lbs costs 30 points in the current rules. We can make that same move in Basic Lift cost the same amount. So Lifting ST 20 to Lifting ST 32 costs 30 points.
Total it up, and going from ST/HP 20 to ST/HP 32 should be 12+25+30 = 67 points for 12 ST/HP. We’ll call it 5 points per level, which pleases pentaphilia as well as acknowledging that damage especially isn’t worth what it used to be.

The breakdown is 1 point per HP, 2 points per point of Striking ST, and 2 points per point of Lifting ST. That again works: Lifting goes up faster than it used to so it’s worth more; damage is less valuable because it scales slower and flatter, so it’s worth less.

What about new ST/HP 100? That’s going from ST 20 to ST 100, or +80ST, which will cost 400 points. You’re lifting more than a ton with Basic Lift alone, but your damage is only about 8d thrust, and 8d+16–> 12d+2 swing.

# Parting Shot

A lot of the games in which I play lower the cost of ST anyway. 5 points/level or even 7 points/level seems like a common value. The trade-up with the higher resolution but increased scaling for lift provides a bunch of small steps with which to differentiate between characters by virtue of physical power.

The real benefit here, to my mind, is the unification of ST and HP values so that they’re explicitly tied to mass and movement capability. When you can say “if your ST and HP match, you’ll move like a human in terms of acceleration, jumping, climbing, etc.”

There will be things that go wrong, of course. The wound thresholds for when one makes death checks might need adjustment – perhaps halving them on the negative end, or just using the usual breakpoints from the Size and Speed/Range Table.

So instead of every -1xHP something bad happens for your life, it might happen at -HP, -1.5HP, -2xHP, -3xHP, -5xHP. Auto-death would thus be at -3xHP, and unrecoverable mess at -5xHP. Note due to doubling that’s about where they used to be.

Characters will be able to take a lot more gunshots to the torso before expiring. One shot to the generic torso with a 5d rifle will leave you reeling but not in danger of KO or death if you have more than 18 HP. One shot with a generic 7d rifle will threaten an average person, but 25 HP and higher (more than about 240 lbs body weight) and you can take one shot.

To the vitals, those hits turn into 51 HP and 75 HP (more or less) respectively, putting Joe Average to -30 (-1.5xHP) and -55 (more than -2xHP but not -3xHP) respectively. So you’re looking at death checks there.

For pistols, the usual 10 HP  per shot (2d–>7 pts x 1.5 for pi+, or 9pts for 2d+2 pi) means that to the torso, you can soak up two shots and still be reeling but in no danger of immediate loss of consciousness. To the vitals, again, we wind up with about 30 HP per hit, so a shot to the Vitals puts you at one death check. So shot placement matters more in this system, which is to the good.

It’s cheaper to get to maximum Basic Lift for regular humans of 80 lbs. That’s 12 points of additional ST, for 60 points, instead of the 100 pts it costs under RAW. Again, that’s not tragic.

Tying HP and ST more closely together is a thing for me, so that doesn’t bother me. Lacking GM permission or superheroic genre, the “you may increase ST to as much as 4 points higher than your mass-based HP” means you need to be about 350-lbs to hit 80-lbs basic lift, which means you’re probably capable of pressing nearly 500lbs with arms alone, and dead-lifting or moving with your back something like 800-900 lbs. Having the mass of a heavy athlete in order to do feats of strength that heavy athletes do? Win – for me.

An equivalence of HP and weight would make a lot of in-game calculations easier, since you could look at strength-to-weight ratios easily by looking at shifts on the size and speed/range table – it’s logarithmic in nature, so looking at differences in the modifiers on the table means you’re doing ratios. Again, this unifies and simplifies the normally complex.

The down side here is that the ability to do penetration-based damage, with thrust or swing, has been utterly and totally nerfed. If a plate harness has just gone to DR 12 where it used to be DR 6, you’re totally immune to blows of less than 2d. For some, this is the reason for doing all this. For others, such as anyone playing Dungeon Fantasy, it may well be a “and that’s why I’m not ever going to do this. Nope.” death-knell.

Oh, and a word about bows and arrows. The switch to damage as sqrt(lifting) probably means that calculations using The Deadly Spring can be based right off of ST. The ST 16 yew longbow (128 lbs draw) does 1d+1 “realistic” damage. That requires a Basic Lift of 51 lbs, which is ST 28 on the new, revised scale. Thrust damage there is 4.1 points, or between 1d and 1d+1. Cinematic damage for this bow was 1d+3. So if a longbow did thr+1 in a realistic campaign or thr+3 in a cinematic one, that would probably simplify things quite a bit.

Crossbows? Heh. The medieval crossbow from The Deadly Spring requires a Basic Lift of 90-95 lbs to span by hand. That’s ST 33 in the new system, for thrust of 1d+2. However, the actual damage of this crossbow is 1d-1, because even though it’s got a draw strength of 740 pounds, the efficiency with which it launches the bolt is low. So crossbows do thr-3 (2) imp damage on the realistic scale, and thr-1 (2) imp for a cinematic one. That two-point differential seems to hold for both types of launcher.

So for bows, you no longer need math – just the table and a ST lookup – to get either realistic or cinematic bow penetration. Injury – which can be quite severe – will be taken care of with the stacking of x2 for imp with x3 for vitals – an arrow to the heart for 1d+1 is no joke, turning into 6d+6 injury, for 27 HP on the average, enough to force KO checks immediately and depending on how harsh one is for bleeding, death by blood loss soon after.

Again – I’m sure there are issue here, but by math alone, it’s not fatally flawed. I’d definitely be interested in seeing this in play for a few sessions.

## More on ST Rolls: Me agreeing a lot with Peter

+Peter V. Dell’Orto made a very on-point comment about my post Go ahead and roll vs. ST. Worth responding to in detail, so I did. His words are in blue-italics, mine in indented black.

I understand the impulse here, and I respect the work you’ve done, but:

– it’s got to be simple.
– it’s got to be a roll, because we don’t just say “DX 14? You just make it.”
– it’s not good if the roll makes another attribute into ST in order to avoid using ST (i.e. HT-based rolls to avoid ST-based rolls)

I tried, and perhaps failed, to make that clear in my Parting Shot. Well, parting fusillade, since I had an entire section there. But yeah, it does have to be simple. Some of the “don’t bother rolling” is to avoid ridiculous edge cases such as when someone pointed out that it was theoretically possible for someone of normal-human size and strength to fail to do a Pickup on a mouse.

That was an artifact of the scaling at fractional multiples of Basic Lift getting quite crazy. PK and I deliberately stopped it at the low end, but didn’t put the line in saying “just don’t roll if you’ve got a ST 10 guy picking up a 2-lb object.”

I agree that all opposed contests should involve a roll. That’s why I pegged the expectation of automatic success at 14 to 16. 16 is convenient because it still allows for a crit fail.

This is why I still have rolls vs. ST, and why I’ll cheerfully normalize around ST 10 like in a Regular Contest of ST. Is it perfect? Not really. Can it be recursive? Yes, but so can any roll (I roll against DX to see how agile I am!). Is it simpler to use a stat on the sheet and not look stuff up? Yes. Done and Done.

Rolls vs. ST that are normalized vs a foe aren’t too bad, I suppose. I don’t like them, but they get the right approach. Rolling vs ST for things like Wrench Limb or to pick up a rock are problematic (the second much more than the first) because of the extrinsic nature of it.

The most useful part of my post, I think, is really the “this is how you can calculate an extrinsic penalty to make the ST roll vs an inanimate object not stupid.”

This is why everyone knows that you can jump over at hex at cost 2, but has to look up their Broad Jump. One you look at, one you look up.

I’d be fine with a replacement, but it’s got to be vastly better if it’s going to be even a little more complex and/or slower to use in play.

Well, I agree. That’s why the opening line of my Parting Shot was “well, this sucks.” Because even though “roll vs ST” has issues, “roll vs HT, then a complicated ST calculation, and if you fail that roll DX, and if you fail THAT roll HT again” is simply awful. It would work as a computer macro (and be pretty damn satisfying, at that). It would not work at the table, for the same reasons – it requires a computer even when things go well (to figure the Weight Penalty of an object and the corresponding Injury Modifier based on lift speed).

TG has the beauty of swapping a single system that’s simple and binary with a single system that is simple and not-binary. That’s the standard I like – does this make my life easier and give better results? Perfect! One of those two? Okay. Makes things more complex and/or gives worse results? No.

This can be an impossible task with ST, being that it wasn’t designed ground-up to do all the things it could do.

This was the core of my findings. ST being extrinsic and not-simple (quadratic in nature) to calculate using the standard GURPS resort for such things (SSR table) means that anything you want to do requires breaking out the calculator (what’s the ST equivalent for a 1,356-lb rock? Gah! 82.3. That’s not helpful).

Even switching to cubic ST, which I explored in a prior post, doesn’t help. It just switches the basis from a square root to a cube root. Booyah? No, that’s no better, and in fact it’s worse.

Logarithmic ST based on the SSR would be better from that perspective, since it’s either a table lookup or something that many (not all) have internalized. Double the SSR value as a penalty has worked well enough in TG in the Grappling Encumbrance Modifier Table. That would pretty drastically reduce the resolution of ST though.

As you note, I don’t see an easy answer there that meets our criteria – fast, realistic, easily playable.

But I’m going to keep looking.

## Go ahead and roll vs. ST

If you’ve read this blog, you’ll see that I’m not a huge fan of ST rolls. I prefer using comparative ST (or even Basic Lift) to calculate a modifier, and then rolling against . . . something . . . with that modifier applied.

In fact, that’s what Control Points (from Technical Grappling) basically are: a proxy for the power of your grip or applied force (damage analog) that either apply a penalty directly (often at -1 per 2 points) or can be spent to apply penalties 1:1, which makes them similar to thrust damage in progression and power.
But saying, “Oh, just roll against Skill with ST as a modifier” does have a drawback, in that it might privilege DX and the cheaper skill even more than usual – and if you can pit skill (at 4 points per level) vs. ST (at 10 for “full” ST, though only 3 for Lifting ST) mostly you’ll win by picking skill.
And yet, one of the reasons that Control Points and the Training Bonus were priced the way they were in TG was to keep ST cheaper – especially for multiple skills – as a way to make your grappling life better. All things being equal, the stronger fighter will win.
In fact, here’s a pull-quote from George Silver on the topic (p. 3 of TG):

Of the single rapier fight between valiant men, having both skill, he that is the best wrestler, or if neither of them can wrestle, the strongest man most commonly kills the other, or leaves him at his mercy.
– George Silver, Paradoxes of Defence

OK, so blah, blah – it’s good to be strong. But I hate ST rolls, because I think rolling against an extrinsic quantity is dumb. If you have a ST 15 man trying to lift a rock, he’s either got the ST to do it, or he doesn’t. Rolling ST to see if you can apply ST doesn’t work well – it’s basically recursive. What about penalized ST? Meh. Still rolling against a quantity not normed to a 3d6 roll.
So what can you do?

Roll against ST anyway

It’s possible to adjudicate this with a ST roll, but you’re going to have to be lavish with penalties. First, if we look at the rules for lifting things, found on p. B353, you can see that simply by taking Ready maneuvers, you can pick up (in two seconds) one handed a mass equal to twice your basic lift.  In two hands, but taking four seconds, you can hoist up 8xBL.
Well, if the first lift takes two seconds on the average, then you’re rolling against a 10. If the second lift takes 4 seconds, you might be rolling against an 8.
Can we rationalize this? Well, it has to scale, so that a ST 40 creature and a ST 10 creature both exerting themselves at 2xBL have the same odds of success. So a ST 10 creature needs to be operating at no penalty, while ST 40 needs to be operating at -30.
So that means that lifting penalties must also be extrinsic. That is, the penalty for lifting a 500-lb boulder is independent of anything else. That’s actually darn handy.
After hacking at it for a bit, turns out that the right absolute penalty to make that work is

10 – ST equivalent of lifted weight *  sqrt(2)/2

So in order to normalize all ST rolls properly, you convert whatever weight is being lifted into an equivalent ST using the usual Basic Lift formula (ST = sqrt (5xWeight)), multiply it by 0.7 (call it 0.7), and subtract that from 10.
OK, now that’s for a 1-handed lift. The two-handed lift works out to a skill of 8, but much higher lift multiple. Do we wind up with a different scaling? I’m sure we do. Will it be easy to parse out? Let’s see. Yep, the trend is different, but you can relate to it.

8 – ST equivalent of lifted weight * sqrt(2)/4

OK, so the first number is the skill roll required, while the divisor for the sqrt(2) term incorporates the number of hands (2 instead of 1). The 8xBL vs 2xBL comes into play with the ST-equivalent calculation.
Issues, Issues

There are some clear issues with what’s going on up there, though.
For one, the faster you do the lift, the lower your penalty. This is an artifact of the starting conditions: the light, one-handed lift happens in two seconds, while the heavy, two-handed one takes four. But the target number can be seen in the table to the right.
The faster you lift, the higher your target, and so perversely you have a higher chance of a burst lift than you do a slow-and steady one.
Even so, heavy one-handed vs heavy two-handed, both in the same time, at least goes the right way. Pushing 160 lbs at ST 10 in one hand vs two looking for a two-second lift, you’d get:
ST-equivalent: sqrt(5×160) = 28.28, and multiplying by 0.707 gets about 20. Dividing that by two for two hands is 10.
Two-second lift: That’s just a target of 10. So you’re at -10 to do this lift 1-handed, and no penalty to do it with two hands.  (10-20 vs 10-10, for -10 and 0 with one and two hands).
From there on, just roll vs. ST with that penalty. Success means you lift the weight. And failure . . .
Lift Fast, Get Hurt Fast

The problem with the fast lift is that you’re risking an injury or out-of-control condition. So if the penalties for lifting faster are lower, because you’re expecting fewer fails before you succeed, then we’ll need something to counterbalance that. Something where the faster you go, the more likely you may get hurt.
Let’s look at our two lifts above, 160 lbs with one and two hands. The penalties for a 1, 2, and 4 second lift (implying target numbers of 16, 10, and 8) would be -4, -10, and -12 for one-hand, and +6, 0, and -2 with two.
Yeah, so we definitely have issues if we just use this to roll vs. ST. We need a “did you hurt yourself” check first, and only then a “did you complete the lift” check.
So we’ll need something that says “heavier is worse, faster is worse, and stronger is better.”
So let’s look at ST – Target Number – Lifting Difficulty:
ST: What it says on the tin. Your ST score.
Target Number: the same thing you pick from the table above
Lifting Difficulty: ST equivalent of lifted weight * .707 / Number of Hands

Oh, and by-the way: I don’t think a 4-armed creature gets 4 there. It’s either 1 for one hand, or 2 for two-or-more.

So an average guy (ST 10) trying to lift 40 lbs (ST equiv of 14.14, penalty of -10 in one hand) in two seconds (target 10) will have a ST roll of 10 to lift it, but an injury penalty of 10-10-10 = -10.

That’s a hefty penalty, and honestly a HT 10 guy shouldn’t be worried about injuring himself here, because right now, he can lift that same 40-lb weight with two Ready maneuvers and no risk of injury. That suggests a net roll of 14 to 16, Or a bonus of something like 15 to the quantity above.

So let’s try that for a ST 20 guy, who should be able to lift 160 lbs in one hand with that same ease.

ST: 20
Target Number: 10
Weight Penalty: -20 (this is independent of ST, which is the only good thing about it)
Injury Modifier: 15+20-20-10 = +5

OK, good. Not surprising, but good. Now, if he wants to make that same lift in one second (target 16 – ‘you only fail on a critical miss’ territory’) that would be:

ST 20
Target Number: 16
Weight Penalty: -20
Injury Modifier: 15 (constant) + 20 (ST) -16 (Target) – 20 (lifting difficulty) = 35-36 = -1.

So to do it in two seconds a prospective HT check would be at HT+5; in one second with little risk of failure you’d roll at HT-1.

That doesn’t seem like crazy talk. It does seem like way too much calculation to pick up a rock. It also makes me say Eww. At least two rolls – maybe three – per turn in order to lift something. Well, these are the trials and tribulations of wanting to keep rolling vs. an extrinsic parameter.

So, what happens if someone with ST 10 wants to lift 220 lbs in two hands, taking a target number of 7?

ST: 10
Target Number: 7 (check the table above)
Weight Penalty: 220 lbs in two hands is -11.7, call it -12
Injury Modifier: 15+10-7-12: 25-19 = +6.
Lifting Difficulty: 7-12 = -5

So taking one’s time will eliminate the possibility of injury (roll at HT+6), but you’ll roll at ST-5 to make the lift . . . 22 seconds to move BLx11.

Let’s say that a failure by 10 means you risk injury or lose control of the weight. So you make a DX check, and if you make it you can drop it safely. If you fail, you make a HT check or take damage.

Parting Shot

Well. This kinds stinks, really.

To make an extrinsic roll make sense (Roll vs. ST to lift the weight), then other weights need to be put in the same terms. That’s not bad. Each weight can be simply converted to a Weight Modifier for a one-handed lift. Halve that penalty for a two-or-more handed lift.

But the rest? The sequence would go:

1. Do Math
2. Roll HT to see if you hurt yourself just applying the initial force.
3. If you don’t hurt yourself, start making ST rolls.
1.      If you make the roll, you complete the lift.
2.      If you fail the roll, but not by 10+, you’ve not hurt yourself but you didn’t complete the lift.
3.      If you fail by 10+, you botch the lift. Proceed to 4.
4. Botched lift: Make a DX check. If you make it, you abort the lift successfully. If you fail . . .
5. Make a HT check. Fail it and you injure yourself.
Up to three rolls just to lift something? Even if you push the boundaries of target number, ST equivalents, injury and whatnot, you’re still doing way too much work here.
So what do do?

The concept of a Weight Penalty makes sense. It’s the ST-based equivalent of a multiple of Basic Lift. But what you really want to do here is to take a “multiples of basic lift” approach for the entire thing, and calculate a penalty.
Then, you want to roll against something. 1xBL should be pretty much instant success with one hand – say +4 to +6. 2xBL should roll against a 10. 8xBL with two hands rolls against an 8.
If we play a bit, we can use the Size and Speed/Range Table. The Lifting Target for a given multiple of Basic Lift works out surprisingly well for 2x the Range value for that multiple. Target numbers are also sensible: 10 for 1-H lift and 15 for 2H lift. If we tabulate that, we get
Red means you can’t even roll to lift it. But maybe you add 5 to it if your goal is to “shift slightly.” So that you need a crit with two hands to shift 50xBL slightly (you’ll be trying it for 30s or so), but with one hand, you can shift about 15xBL a bit.
So that’s at least “make one roll, and on a failure, maybe you need to check to see if you drop it or injure yourself or something.” It scales automatically, since it’s based on an NxBL figure. And it uses a table that every GURPS player has.
What about ST vs ST?

This is also force on force, and the best way to look at it is probably a ratio of BL to BL. That provides a good assumption that whatever the right ratio of effort is (I can fight at 6xBL!), it’s common to all. So ST 10 vs ST 20 has the ST 10 guy resisting 4x his own BL, while the ST 20 guy is pushing back against only 0.25xBL to achieve “balanced” levels of force.
If we use the same scale as pushing vs a static object, then only one party should roll. If I try and split it into two rolls (so each party gets their own lookup), that is perhaps more satisfying, but it creates some artifacts.
So I’m just going to have the PC roll vs a look-up table result. The GM can either assume that he’s rolled a 10 vs. a 10 target (and leave it all in the hands of the PC) or actually roll if more variability is desired.
But the resolution is finer: if the foe is twice your ST (or half of it), it’s not a contest at all. You just lose. So the gradations of the roll look like this:
You could easily turn this into a ST vs ST table (I did that too). But basically, take the foe’s ST divided by the PC’s ST and square it. Look that up as the BL multiple on the SSR table, double the modifier, add that to 6, and roll. If you make the roll, you win. Fail it, you lose. If the GM also wants to roll, it’s whoever makes it by most, or fails by the least.
Other Possibilities

The only other possibilities for contests of power (or at least those that are strongly influenced by power) are DX and HT. DX makes sense in some cases – such as combat skills, which take account of relative ST through a damage roll (or a control point roll, in Technical Grappling).
HT seems good at first – hey, if you’re robust, you can push your limited ST farther without buckling.
That’s all well and good, but HT is more frequently fatigue and exhaustion rather than structural power, and doing it that way means a ST 10, HT 20 guy has a super-duper advantage arm wrestling a ST 10, HT 10 guy. That’s probably not desirable.
So I think the flat values explored above are the right mathematical way to go if you’re replacing ST rolls with ST-modified target rolls.
For keeping ST rolls, it’s obviously a heck of a lot more complicated, and involves finding another extrinsic quantity – in this case force or weight – to subtract from the roll before you roll dice. The nice thing about that is for very low (or high) weights, if your net roll is 19 or higher (say), you can just say “yep, you grabbed it.” If it’s less than 3, “you can’t lift it.”

## Rescaling GURPS HP – some car thoughts

As as was driving in to work, I was thinking about the relationship between ST, HP, and damage. One of the potential solutions people have talked about to bring fisticuff damage, especially swing damage, in line with firearms has been to double HP and DR scores, add a (2) to all pi damage, and call it a day.

My post today is not about that.

It’s really just a realization that one of the impacts of having reasonable HP and mass relationships is that doubling the HP that a character has very, very much widens the range of HP scores that are game-relevant.

If you look at most humanoids in most games (not all games, and not all humanoids, of course. This is GURPS) they’ll tend to run from the 80-400 lb range.

Female champion gymnasts run from about 80-125 lbs. Pro jockeys tend to be in the 100-120 lb. range. So on the low end, that’s not bad.

 William Perry, Adventurer at Large

Andre the Giant clocked in at 500-650 lbs, depending on the source. So there’s an argument for going even higher.

William “The Refrigerator” Perry, an American Pro Football player, was 335-385 lbs, but could dunk a basketball and ran a 100-yd dash in about 11 sec (Sprint Move 9, or regular Move 7.5). This is more in line with a “professional” GURPS adventurer.

At the normal scale, the gymnast is going to be a low of 9HP high of 10HP. Jockeys will all fall in the 10HP range. Most men in the 150-200lbs range are all 11 HP. The Refrigerator is 14 HP. Andre clocks in at 16 or 17.

Parting Shot

Doubling the HP totals means your low end gymnast is 17 HP, but the high end is 20HP. Jockeys are still all going to be 20HP (more or less), but from 90-150 lbs (for example) you now get HP from 18 to 21, and in the adventuring range doubles (as expected).

I like that this carries with it the potential for more differentiation in a lot of things. Characters are the heart of the game, and from a “what makes for a sensible HP number for various folks” perspective, having a wider range of useful values is good.

From a damage and DR perspective, now we have the identity 20d(2) = DR 140 = penetration of one inch of RHA steel instead of 20d = DR70 = penetration of one inch of RHA steel. That keeps all of the armor and gun damage in the game where it should be.

It would provide more differentiation using The Deadly Spring for bows, too, so that you don’t have to get crazy-town increases in draw weight to increase bow penetration by a point (assuming you don’t also give arrows pi damage, which I would not), since the resolution is higher.

This isn’t something I’d just go do if I started a game tomorrow. But I couldn’t help notice that the increased resolution when translating weight (and Basic Lift, a topic of recent interest) to HP was pretty friendly.

## Cubic ST for GURPS?

Over on the forums, Wavefunction threw down a concept: use the cube of ST for Basic Lift, and therefore power, instead of the square.

I’m sure there are lots of biomechanical reasons for not doing this. But he noted a few advantages right off the bat, most notably that ST is equal to HP, and HP go as the cube root of mass, so that scaling the two together means if you have a ST 50, HP 50 giant, he will have the lift required to move his weight just like a human. More or less. Close enough for RPG purposes.

It also compresses the ST scale like +Sean Punch‘s recent article about log ST does.

A quick table in the PC-centric range of ST 6 through ST 20.

So what this does is compress PC lifting strengths into the range of 9-16 instead of 8-20. Each point of ST means more than it used to, but at least within the realm of human-centric PCs, it’s not crazy-town.

The implications on carrying capacity go way up for equivalent points in the PC range of 10+. So at CubeST 14, you’re getting maybe 7-8 points of Lifting ST as a bonus. That won’t break anything.

Damage Scaling

The implications of this on damage scaling? Still interesting. At human ST scales, ST 16 is darn strong – equivalent to QuadST 20 – but now punches for 1d (thr-1) instead of 2d-1, and the off-the-damage-table swing base is 2d+2 instead of 3d+2.
Alternate damage scaling? Sure. If you decide that swing should be about 1.5x thrust, that pulls ST 16 down to 2d-1 swing, or about DR 6.

If you wanted thrust damage to be related to basic lift and be quadratic in intensity, so that it scales with firearms, you could do something like “points of damage is sqrt (BL) * Constant.” If you adjust so that damage at ST 16 is 2d and ST 10 is 1d, you can see that works out OK, with CubeST 20 being something like 3d-1 swing . . . and that’s for someone that can lift nearly 3/4 of a ton, and clearly non-human.

Inclusive of Body Weight?

HP are now matched directly with mass – and that has its own value. To the point where you might be able to start doing interesting things with ST-to-HP ratio and log scores and all sorts of fun things.

A reminder based on the HP–>Mass conversion is that the assumed HP of a complex, Unliving object is 4 x cube root of weight in pounds, or 2x cube root of weight for complex, living objects. Like PCs. Turning that around, and treating HP as mass only you get Mass = 1/8 x (HP cubed).

Or:

 HP Lower Upper 5 11 21 6 21 34 7 34 53 8 53 77 9 77 107 10 107 145 11 145 190 12 190 244 13 244 308 14 308 381 15 381 465 16 465 562
I’d have to play more, but it seems that one could look at figures like “maximum physical capacity” as the ability to move yourself plus the ability to move stuff. That is, some multiple of basic lift plus you assumed mass for HP equal to ST. So ST 10 might have a total lift capacity of 125 lbs (the expected midpoint for HP 10 for mass) plus 15xBL (the max you can carry on your back without lifting it there yourself) for a total lift capacity of 425lbs. That includes the person.
That probably motivates some funky breakpoint behavior, so I won’t charge down that road. But it would allow some very interesting calculations based on Strength-to-Weight ratio directly. Jumping vertically would be the equivalent of throwing yourself, and ST to mass-based HP ratios could be used to determine lots of physical feat results.
Of course, you wouldn’t do math like that at the table. You’d look ST and HP up on the Size and Speed Range table (which is a logarithmic basis), and use the difference between the two to determine results – because log subtraction is division, so you’re doing easy ratios.
Parting Shot

I think the proposed rescale bears serious consideration for game balance and normalization purposes. You get more “bang” in lift terms from lower ST values, and if the GM is willing to fairly rigorously enforce ST and HP bounds (your ST should be within 2 points of your mass-based HP would be a decent rule of thumb for human normals) it should work.
Someone wants to buy ST 20 as a human normal? Lift 3/4 ton? Sure. You’re 18 HP, which means you weigh between 670-790 lbs. Oh. Too heavy? How about you clock in at a fit 325, Mr. Conan, for 14 HP and ST 16.

## Revisiting ST (Strength) Rolls in GURPS

Edit: I do a lot of GURPS writing, but my audience is now broader than it used to be. That’s all to the good, of course. But: ST is Strength in GURPS. HT is Health. DX is Dexterity. HT and DX are 10 at the average, and relate to physical and mental robustness to physical effort and injury for HT, and the ability to control your body’s motions and objects – such as weapon attacks – for DX. ST is directly related to damage – each extra point of ST gives roughly an extra point of swung weapon damage – and sets your hit points (equal to ST) and lifting capacity (a function of the ST squared). So while a T-Rex and a squirrel can both have DX 11, HT 10 (as an example), that T-Rex might have ST 50, and the squirrel ST 1 or ST 2. One can and does make die rolls against ST in some cases, and in the past, I’ve noted that it wasn’t my favorite game mechanic.

Do I still not like ST rolls?

Yeah, I still think they need to die.

But a while ago, I penned a bit on grappling at low ST that had the right kind of thing going for it.

Recently, I’ve been noodling more on this, and there are some interesting concepts that have come to me that are not giving completely stupid results when I start to apply them.

So this will be about building the idea to see what happens.

Power Ratio

The key bit for a lot of this work is the concept of power ratio, or strength-to-weight ratio. The key bit, of course, is that a lot of the performance stuff we’re dealing with here is simply a measure of how much force you can apply (a function of ST), measured against the resistance to that force (an opposing fighter’s ST, or the weight of something you’re trying to lift).

Now, ratios in games can suck. But you can turn a ratio into a sum using logarithms, and a log-based table (the Size and Speed/Range table) is at the core of scaling in GURPS. So if there were a number that related to force or weight, then a quick comparison would then give you a figure for overmatch – basically whether you’ve got the ability to muster enough force to make the job easy or hard.

HT and DX

The short version here is never roll against ST. ST provides a modifier for what you’re trying to do. But if you’re trying to see if you have the fortitude to pick something up, or are straining at max power against something, you’re rolling against HT. If you’re trying to manipulate things with precision, that’s DX, again penalized by how hard you have to work to simply lift it.

For lifting, higher HT should

Key Numbers

Whatever scaling I decide to use, the results should make sense based on normal GURPS results. Moving around something less than your basic lift should be easy. More than 8-10xBL should be hard. 15xBL (carry on back) More than 50x Basic Lift (the ‘shift slightly’ limit, p. B353) should be impossible or close to it.

The other thing that will have to be guarded against is having HT become the primary driver of lifting power rather than ST. This would be easy to see – if the penalties for climbing up a power ratio are mitigated more strongly by increasing HT than ST, you can have a case where it’s better to be ST 10, HT 20 in terms of lifting power than it is ST 20, HT 10.

Scaling

As noted before, “use what’s there” when you can. This means that if we need a log table and we can get away with it, easy modifications to the Size and Speed/Range Table are where it’s at.

That we need to go from 1xBL as easy to 10xBL as hard suggests that the usual -6 penalty for a x10 increase in difficulty isn’t enough. Since the practical range is really 1xBL through 15xBL (7 steps on the SSR table) and we want 15xBL to be really, really hard even for someone of superlative HT, having x10 be somewhere like -9 through -12 would be in the right range.

-9 per x10 is 1.5x the SSR progression. That’s OK, but if you’re going to do logs and math, at that point you might just want to say 10xLog(Weight) so you can simply push one button on a calculator.

But -12 per x10 is interesting, because what it says is that you will need some sort of boost – lifting training or such – to HT rolls in order to max out lifting ability. That’s not tragic. We’ll have to be somewhat careful, though, as the typical penalty to act under 10xBL is -4 to Dodge. Since Dodge is based on Basic Speed, which it itself (DX+HT)/4, then to get to Dodge -4 based on penalties that are applied to each of DX and HT requires around -16 in total penalties, or -8 to each of DX and HT. -9 would work as well, and -10 would be Dodge -5 instead of -4.

So the -12 scaling rate would work OK if 1xBL were a roll at +4 and 10xBL is -8. Again, that seems to not be crazy-talk.

And going from 10x BL to 50xBL? That’s another 4 steps on the SSR table, so it’d be an additional -8 penalty . . . -16 if we pegged the scale as it was before (that puts no penalty as 2xBL, more or less, for what it’s worth).

If we want to match the current encumbrance scaling, we’d set the no penalty level to 20 lbs (1xBL) and -8 at 200 lbs (10xBL). 50xBL would be -14 on that scale.

The two scales are incompatible. Eventually, a choice will need to be made – likely making a straight-up roll vs some HT-based formula the equivalent of “combat” ability – do what you want, in one second, with no preparation, bracing, etc. And the equivalent of an All-Out bonus (maybe, hopefully equal to the usual +4 for AoA) to add the need to brace and prepare in order to lift high weights.

HT roll as a Parry equivalent

Basing the resistance roll for lifting on straight-up HT makes increasing HT too powerful. Making it something like 3+HT/2 helps mitigate it, as well as taking the bite out of lower HT.

So if we set zero penalty at 1xBL for ST 10, that is, 20 lbs, with that same scaling, some interesting things happen. I’ll explore those at a later date. So how are the results from a consistency perspective?

If we look at 3+HT/2 for a point where you’re rolling vs a 10 (50% chance to snag something easily with no bracing or prep), going from HT 10 to HT 20 boosts that (again, for ST 10) from 30 lbs (1.5xBL) to 70 lbs (3.5xBL). That’s for 100 points. For that same 100 points, you get to 120 lbs, which is 4x higher than the 30-ish lbs. you get at ST 10. So at this juncture, it’s still more efficient to boost ST than HT.

Lifting Skill

For a boost to HT based on training, when just looking at making the lift (can you do it on that attempt), I’d probably look to the Training Bonus used in Technical Grappling. So actual lifting skill in excess of DX would grant a bonus to the roll above (in effect, double bonus to HT).

One could/should also consider NOT making it a straight roll, so that HT 11 and a +3 training bonus for Lifting skill at DX+2 is worthwhile – it pushes you to the equivalent of HT 14, and helps out with that “but odd values of HT suck for breakpoints!” thing.

In fact, I kinda like that.

Parting Shot

The dynamics of HT and ST just got a bunch more complex. The good news of eliminating ST rolls is balanced by a whole lot of potentially suspension of disbelief generating emergent behavior as the interactions of all of this are realized.

This is a bit of a ground-up redsign of the ST and encumbrance rules. The usual penalties and bonuses for having a certain multiple of BL for break points and its impact on Dodge could easily turn into an all-out penalty to skill as well. That would turn heavy armor from “oh, that’s heavy, it impacts my Dodge” into “that’s crippling and hits my ability to do anything to a ridiculous degree.”

Perhaps easy to fix: that weight only impacts move and dodge, perhaps, and you only suffer DX penalties when trying to manipulate the entire weight. So you might be at -4 to DX and HT trying to throw  50 lbs of armor, but no penalty to DX and -2 to Dodge while wearing it.

The next step in bringing this into an actual system for rules would be to turn this around, and instead of using a spreadsheet to look at well-paced increments on the Size and Speed/Range table, to think about setting things up in terms of penalties based on Basic Lift.

The numbers will look weird. You’ll be looking at a 12-step progression – basically twice the resolution of the usual SSR table, and that means the progression to be memorized looks like this:

 0 -1 -2 -3 -4 -5 -6 -7 -8 -9 -10 -11 -12 1 1.25 1.5 1.75 2 2.5 3 4 5 6 7 8.5 10

with the bolded numbers being the usual SSR table.

It’s a fairly punishing progression. A 50-lb load against a 20-lb basic lift is -5, which will wind up being about -2.5 to Dodge. That’s higher than the roughly -1.5 it is now (it’s really -2, since you’re above 2xBL). Favoring the defense by dropping fractions will be the order of the day here – already a departure from GURPS standard procedures. That would move the Dodge breakpoints to

-1 to Dodge at higher than 1.5xBL (that’s a break for the player)
-2 to Dodge at higher than 2xBL (break even)
-3 to Dodge at 3xBL (same as usual)
-4 to Dodge at 5xBL (harsher than RAW)
-5 to Dodge at 7xBL (this level of penalty doesn’t even exist)
-6 to Dodge at 10xBL (quite a bit harsher than the usual -4)

At least that value is independent of HT; it’s just power ratio based which is good. The ability to lift weights at a given power ratio, at least in one turn? That becomes strongly HT-based.

What that might turn into is to leave go any temptation of inflicting injury on a failed HT roll. Instead, you’ll be saying that a successful HT roll completes the lift. A failed one (maybe fail by less than a certain margin) means you move the weight but not to the full range of motion (that might be how we get from 10xBL to 50xBL for “shift slightly”). Only on a crit fail, or some sort of double botch (start the weight moving, then fail it, then fail a DX or HT roll to keep it stable or immobile or something) might you pull something, or try and drop the weight but drop it on yourself instead.

This is how I tinker with rules when I’m in full-on tweak mode. It ain’t pretty. It involves lots of trial-by-spreadsheet and Goal Seek and trial-and-error.

It usually winds up somewhere I like (see The Deadly Spring, The Last Gasp, On Target, etc). But sometimes, it doesn’t