[DF] Caltrops

[goblingooner]

Hi, I'm a GM running a Dungeon Fantasy campaign. My tricky thief uses caltrops but I am not sure quite how they should work.

First, they there are two mentioned ways they are detected: Vision-2 in Dungeon Fantasy 1 p.25, or Vision-(margin of victory when setting the trap) in Dungeon Fantasy 2 p.12.

Second, they can deal a ton of damage to high ST creatures. A really high ST creature (like the giant gorilla from Monsters 1) can be single handedly defeated by a caltrops because they cripple the foot and the monster falls onto a hex full of caltrops. As GM, I just assume that extra caltrops due to margin of failure deal damage to the torso. It just doesn't feel right for a battle to end so abruptly for such a simple trick.

Third, what happens after a caltrop trap is stepped on? Do combatants still have to make the vision rolls like in Dungeon Fantasy 1? Or does it become obvious or triggered and therefore useless like in Dungeon Fantasy 2? And if the latter, does it apply to all the trapped hexes in the room or just the triggered hex?

Thank you to anyone responding to this.

[vierasmarius]

You may be interested in the entry for Caltrops in Low Tech (pg 123). It's more detailed than the DF treatment, and one thing it includes is a maximum injury of 2 points per caltrop. This should help prevent large creatures from instantly crippling themselves. For the note in DF 2 about caltrops, I'd only use that for deliberately hidden caltrops, and keep the Vision-2 roll if they are simply scattered on the ground.

Honestly, I'd prefer if Caltrops used a to-hit roll (base "skill" of around 6, plus the Rapid Fire bonus for the number of Caltrops in the hex, plus the target's SM). A Vision roll (with a moderate penalty, but a bonus based on the same Rapid Fire bonus) would let someone notice the Caltrops, and either walk around them or pick their way through. Of course, that may be too much complexity for DF.

[Peter Knutsen]

Originally Posted by goblingooner

Second, they can deal a ton of damage to high ST creatures. A really high ST creature (like the giant gorilla from Monsters 1) can be single handedly defeated by a caltrops because they cripple the foot and the monster falls onto a hex full of caltrops. As GM, I just assume that extra caltrops due to margin of failure deal damage to the torso. It just doesn't feel right for a battle to end so abruptly for such a simple trick.

I'd assume that caltrop damage is based on the assumptopn that the victim is stepping on the caltrop, that is is putting one foot down on top of the caltrop with his entire mass divided by X behind the step, where X is some factor based mostly on the number of legs he has (e.g. X=2 for a walking human, X=1 for a running human).

Falling down, due to havnig had one's foot crippled by 1-2 caltrops, onto a floor covered with many more caltrops, should not cause the full damage for each additional caltrop. That sounds completely unreasonable to me.

[BrockNicholson]

I don't think it is particularly unrealistic or unreasonable for a monster or person to be killed or incapacitate by being stabbed numerous times over a large portion of their body. Caltrops are essentially a small knife rigged to always point up. That could do some serious damage stuck into a body, especially if they have been driven in by the force of that body falling.

[sgt.sargent]

Originally Posted by vierasmarius

You may be interested in the entry for Caltrops in Low Tech (pg 123). It's more detailed than the DF treatment, and one thing it includes is a maximum injury of 2 points per caltrop.

Seems like that would make it reasonable that on a fall you'd be taking falling damage, with the usual hard or soft ground, with one point of that damage per caltrop being impaling (making 2 points of injury per caltrop). That way, falling on a pile of 2,000 caltrops doesn't do 4,000 points of damage, virtually exploding a normal human, unless it was quite a big fall.

[Kromm]

Could be good to read the rules, of course . . .

Victims who miss a Vision-2 roll step on a number of spikes equal to margin of failure.

So for the average Per 10 human rolling average dice (10 against an 8), two caltrops. For a real disaster involving a roll of 18, 10 caltrops.

Each inflicts thr-3 imp – based on his ST

For a ST 10 human with thrust 1d-2, that's 1d-5 apiece. Since it's impaling, and does 1 point minimum (p. B378), you can read that as 1 point per caltrop.

– to the foot.

Let's read p. B399: First, to a foot, impaling does ×1 wounding, not ×2. Second, anything beyond the minimum to inflict a crippling injury is lost. For a foot, crippling involves injury beyond HP/3.

So . . . our victim with ST 10 has HP 10, and injury over 10/3 cripples his foot. That's 4 HP. Assuming no armor, not even DR 1 shoes, our victim takes somewhere between 2 and 10 1-point caltrop wounds. If he steps on 1-3, he takes 1-3 HP but isn't crippled. If he steps on 4+, he takes the maximum of 4 HP and is crippled. No further injury can occur.

Note carefully that nothing is said about falling down and getting speared all over! Someone with a crippled foot is forced to the ground (p. B421), but nothing says he must land in caltrops. That's a reasonable conjecture, but then it's no less conjectural to declare that the rules assume the exceedingly high ground pressure of a foot.

If a whole person were to land on these little ninja caltrops, he'd take falling damage from roughly half his height (not his full height, as he isn't floating at head level!). For a ST 10 Joe, that's 1 yard. From pp. B430-431, this would give velocity 5, and he'd use twice his HP for the hard surface, for 1d . . . which would be impaling, but also halved for being spikes (bottom of p. B430). Thus, damage would be 1d/2 impaling, or 1-3 points of damage, doing 2-6 points of injury to an unarmored man. This is the sum-total effect of an indeterminate number of caltrops, not a per-spike figure.

So the risk of people exploding is highly exaggerated. At worst, Joe Blow suffers 4 HP, gets his foot crippled, keels over and takes 6 HP more from the landing, and is at 0 HP from all the blood loss. If Joe has DR 1 shoes, none of this happens.

It's true that big monsters might be hurt more, but they tend to have DR, Injury Tolerance, and/or lots of HP. If a flesh-eating ape (ST/HP 17, thrust 1d+2, Per 10, DR 1, SM +1) screws up badly, it takes 1d-1 per spike to the foot, which with DR 1 averages 1.7 HP/spike. It needs to suffer 6 HP to cripple its foot, so that's three or four spikes. If that happens, and it falls, it falls from half its height (call it 2 yards, barely, at SM +1), which gives velocity 7; with 17 HP, doubled for "hard," that's 2d, then halved to 1d for impaling. Worst case against DR 1, this is 10 HP of injury. Thus, maximum injury is 16 HP out of 17 HP, plus a crippled foot.

[Peter Knutsen]

Originally Posted by BrockNicholson

I don't think it is particularly unrealistic or unreasonable for a monster or person to be killed or incapacitate by being stabbed numerous times over a large portion of their body. Caltrops are essentially a small knife rigged to always point up. That could do some serious damage stuck into a body, especially if they have been driven in by the force of that body falling.

Caltrops aren't big, though. As far as I know, they're more like large needles, with each point a couple of centimeters long. They're unlikely to pierce anything important.

A historical ninja would cover the caltrops with poison, though. Or feces, probably partially rotted feces if possible.

Even if he didn't have time to do that, whoever then stepped on the ninja's caltrops would stop and wonder. His first inclination would not be to assume that the caltrop he had stepped on was in any sense of the word clean. He'd be worried silly. Similar to the ninja use of shuriken, although those were also thought (correctly or not, I don't know) to have rusted edges, which opens up fun and hypychondric speculations about tetanus (AFAIK always lethal at medieval TLs).

[Anders]

Anyone who has stepped on a d4 knows what horrible weapons they are.

[roguebfl]

Originally Posted by Asta Kask

Anyone who has stepped on a d4 knows what horrible weapons they are.

non gamers it easyer to describe them as non blunted jacks 8)

[Kromm]

Historically, caltrops deployed as battlefield weapons were intended mostly to lame military beasts (horses, camels, even elephants). Animals were less likely to recognize them for what they were, and were difficult to steer around them when charging. Caltrops broke up chariot, cavalry, and camel charges fairly effectively.

In modern times, caltrops are used mainly in a security role, and are effective against civilian vehicles with standard tires (they're not especially useful vs. solids, a CTIS, or tracks). The "spike strip" is the usual variant. I believe that the hollow-quill design sometimes used in strips is also found in tetrahedral caltrops, though.

In either case, they're not particularly effective against men on foot (who can see them), or men in armor or good-quality boots (who rarely develop enough ground pressure to push the spike through the sole). A lot of the mythology surrounding them comes from the fact that they look wicked and could hurt a barefoot man or someone in light footwear.

This mythology is especially strong where makibishi are concerned. It's definitely true that these were employed as defensive weapons in battle in feudal Japan. The catch is that in that time and place, most troops – even the samurai class – wore sandals woven from straw, which offered no useful resistance.

Consequently, the idea that ninja might have used tetsubishi as pursuit deterrants (not as battlefield weapons or anti-vehicular devices) is plausible. However, there isn't a lot of evidence to suggest that Japan was overrun by ninja pitching these things into the paths of their enemies. It's more that ninja were assumed to use any and all weapons and dirty tricks. As caltrops were used in castle defense, and effective against straw footwear, people just assumed that ninja would cast them before barefoot and straw-shod pursuers.

Like a lot of small, spiked things supposedly carried by ninja, it's anybody's guess whether these were really used . . . and if so, whether they were poisoned. The thing with poison is that it isn't cheap or free, and poisoning tiny items to deliver tiny doses isn't really effective, either. As well, an object with points everywhere, intended for hasty use when somebody is chasing you, isn't something you want to poison – too much room for an own-goal.

With some irony, perhaps, I'll add that there's evidence that shuriken were used this way. They stuck nicely in wooden floors, leaving blades fixed in the ground. They were often significantly bigger, and could pierce respectable footwear. Whether they were poisoned is more conjecture, though . . . probably yes, but there's no way of saying with what, or how effective it was.

Source: A great deal of reading on the subject while researching GURPS Martial Arts. See the bibliography. ;)