Friday, April 8, 2016

Monster Details

Two tidbits in relation to Monday's post:

Dragon Breath

Here's my thinking about figuring out how many people get hit by dragon breath in an abstracted combat. The first thing I thought of was: what percent of an arc around a dragon can its cone-shaped breath hit? For red dragons, the fire is a cone 9" by 3" in size. Here's a slice of half that area:

Since this half-area is a right triangle, it's easy to figure out the angle involved: about 9.5 degrees -- so the whole red-dragon cone is about 19 degrees, say 20 degrees for convenience sake. So that means if the red dragon was pivoting its head outward like a random turret it would only cover 1/18 of the surrounding disc, or 1/18 of an opposing party, at a time. That seemed far too little, so I looked for another approach.

The idea I thought then, was this; a smart party would want to spread out as much as possible on the dragon, but the dragon's body is long, so effectively you'll have half of the fighters on one side, and half lined up on the other side (optimally to the attacker's view). Assume the dragon can crane it's neck around and shoot a blast just scraping one side of itself without hurting itself. We know from physical testing that a red dragon cone can hit up to 14 figures in a sparse formation (link). So the conclusion was to rule that a red dragon's breath can hit half of the opposing party, to a maximum of 14 figures. The same rule was used for gorgons and chimeras, with a little math on the smaller areas to give a different maximum figure number (7 for gorgons, 4 for chimera).

Giant Melee

Initially I was surprised by some of the result from Monday, by how few low-level fighters it took to match up against fairly high-level monsters. For example: The table says it only takes 4 1st-level fighters (in chain & shield with a sword and +1 bonus) to be evenly matched against a Hill Giant (with 8 hit dice and a double-damage attack). So as a double-check I sat down and manually scratched out a case study.
  • Giant average damage/round: 7 × 0.65 = 4.55. This gives about a 50/50 chance of the giant killing a man per round; if the fighter's hit points are 4 or below he's dead, if hit points are above 4 (on d8) he lives another round. That is: expect to kill a man every other round.
  • Fighters average damage/round: 5.5 × 0.35 = 1.925. Say on average that each fighter tags the giant for about 2 hit points each round.
  • Giant average hit points are 3.5 × 8 =  28 (OD&D d6 dice, as always).

 Case 1: Giant kills no one with initial rock-throw. By melee round:
  1. Giant kills 0; 4 fighters do 8 hp damage; giant at 20 hp.
  2. Giant kills 1; 3 fighters do 6 hp; giant at 14 hp.
  3. Giant kills 0; 3 fighters do 6 hp; giant at 8 hp.
  4. Giant kills 1; 2 fighters do 4 hp; giant at 4 hp.
  5. Giant kills 0; 2 fighters do 4 hp; giant dead, fighters win.
Case 2: Giant kills one man with initial rock-throw. By melee round:
  1. Giant kills 0; 3 fighters do 6 hp damage; giant at 22 hp.
  2. Giant kills 1; 2 fighters do 4 hp damage; giant at 18 hp.
  3. Giant kills 0; 2 fighters do 4 hp damage; giant at 14 hp. 
  4. Giant kills 1; 1 fighter does 2 hp damage; giant at 12 hp. 
  5. Giant kills 0; 1 fighter does 2 hp damage; giant at 10 hp. 
  6. Giant kills 1; 0 fighters left, giant wins.

You could interleave the 2nd case so that the fighters get initiative on the giant (attack first in each round); they still lose, although it's a closer match, the giant having only 4 hp at the end. But in short the result does check out; the giant-vs-four-veterans matchup has about a 50/50 chance of going either way, depending on whether the giant strikes with its initial rock attack or not.


  1. In AD&D i use the moral rules. Do you need to factor in morale rules in OD&D?

    1. I decided not to do that for this goal of "how many fighters is a monster worth?" metric.

  2. In fairness, the fighters do get a leg up on the original rules in that they're getting d8 hit points while the giant still only has d6 hit points. Reducing the men to d6 hit points would increase the giant's chance to kill one each turn from about 52% to about 58% overall.

    Also, I see you factored in an initial rock-throw, but it killed no one or one man in the test cases. Did you factor in that the rock throw is supposed to be an area attack with a 2" diameter, as a light catapult? By a strict reading of the LBBs, it might not even need an attack roll; Chainmail catapults hit anything they touch, with the exception of heroes and wizards who make their saving throws. Just curious, as on paper the rock throws seems more deadly than your test cases would indicate.

    1. Right about the hit points, that's part of what I wanted to make explicit with this post.

      My interpretation of the rock-hurling is to use the range and rate-of-fire from Chainmail, but not the area-of-effect -- which I consider to be outrageously oversized, and also not have any damage factor explicated for it (just autokill in Chainmail, technically). So: An example of using the MM interpretation of the monster.

    2. True that the MM gives an explicit damage value, but does it actually say that rock throwing is single-target and uses an attack roll?

      I don't have the 1E MM on-hand right now, but I double-checked for the 2E MM and they never actually say what the procedure for thrown rocks is. In the absence of additional information, I would certainly - and certainly did in the past - interpret that to be a "one target, one attack roll" situation, since that was the default for the edition. The reason I bring it up is that looking at the OD&D and Chainmail rules over the last several months has made me question that approach.

      If we wanted to interpret the rock throw without referring to the AD&D MM, there are three possibilities that I consider to be reasonably likely:

      1) Since Chainmail had no hit points - a hit was equivalent to a kill - we could extrapolate that it does 1d6 damage just like every weapon or natural attack.

      2) The rules in Vol-II say that giants deal two dice of damage, therefore the rocks they throw deal two dice of damage

      3) Since fireballs are also treated as light catapult shots in Chainmail, treat rock throwing the same way as a fireball. Specifically, deal one die of damage per hit die of the giant, with a saving throw allowed for half damage.

      As for the the large area-of-effect, I believe that the reasoning behind it is that the giant is pelting the area with a barrage of rocks over the course of the 1 minute round - much as I interpret the catapult itself to encompass either repeated shots from a ballista or springald, or else a crude "grapeshot" type of ammunition shot from a trebuchet, onager, or the like - because let's face it, neither a giant nor a medieval catapult can throw a singular stone large enough to devastate a 20 yard diameter circle.

    3. Edit: Even considering later clarifications that areas of effect should always use 1" = 10' scale, a 20 foot diameter circle is still well beyond the size of a stone that any medieval war engine could hurl.

      Addendum: I also think it could be modeled as a save-or-die effect, if you want to swing a bit in the simulationist direction. After all, if you get hit by a 50 pound rock, there's no armor in the world that will save you. Rogue shot puts kill (admittedly, unarmored) people, after all, and those are only 16 pounds for the full regulation kind! Not to mention the giant/catapult must be hurling at a greater velocity to achieve such range, as even Olympic shot putters can only throw it 70-75 feet. So if one is trying to be realistic about it, you either don't get hit in the first place, or you're at best maimed and out of the battle.

    4. I agree with you that the huge area-of-effect of Chainmail catapults creates major believability problems, that call out for some solution. In AD&D the giant rock-hurling does reference catapults (MM p. 44), but the catapult rules (DMG p. 108-109) no longer reference an area-of-effect, but rather a "target creature" in the singular. They also indicate rate-of-fire at 1/4 per round, an assumption of AC 0, and reference to the scatter table for grenades on a miss. I might not use all of those bits and pieces, but I do think that's a sensible interpretive direction to lay on OD&D.

    5. Mm, that's also getting into the problems of scale that EGG ran up against when he was writing the original AD&D books. It's well-documented that most forms of ballistae, catapults, trebuchets, etc. could hurl 3 or 4 projectiles per minute with a competent crew in parabolic fire. In a one-minute round, a war machine should really have a rate-of-fire of 2/1, 3/1, or even 4/1 per round! This is why I'm inclined to believe that Chainmail is simply abstracting several shots into a single radius attack, as it seems fairly reasonable for three or four stones/bolts to kill several men in close formation - or for ten such machines to kill several tens of men, at the 10:1 non-fantasy scale.

      I also have some nit-picks with his spatial scaling - mainly with the ranges he assigns, since realistically most stone-throwing machines had similar ranges (about 200-300 yards), the larger ones using their extra mechanical energy to hurl significantly heavier projectiles rather than attaining a longer range. Also, his "Light Catapult" projectile being a stone of 1' diameter would weigh roughly 250 pounds, making it among the heaviest stones commonly used in the medieval period. His "Heavy Catapult" stones, stated to be 2' in diameter, would weigh roughly one ton; only the most exceptionally large trebuchets, such as the one that Charles VII is recorded to have commissioned in the 15th century, could hurl stones of this magnitude.

      I was talking about ranges before my digression. The other important thing is that ballistae and other bolt-throwing machines could hit 400-500 yards reliably. This leads me into a rather peculiar idea that I have about Chainmail and OD&D that probably wasn't intended - that "light catapults" and "heavy catapults" should be reclassified as "ballistae" and "trebuchets" while swapping their ranges and man-killing power. The maximum ranges would then be appropriate, and it would reflect the great anti-personnel role of ballistae, springalds, and scorpiones. Possibly this still makes them too deadly - maybe it would be better for ballistae to get the 2" diameter and for a trebuchet to only kill a Line + Bounce like a cannon - but I have not had an opportunity to test such things in-game. Food for thought, though.

      As mentioned, the above deals with parabolic fire, which isn't so useful at short ranges. I would say that trebuchets and the like shouldn't even be usable to fire at individual man-sized targets, though I suppose the AD&D rule does make it sufficiently hard to hit that it's impractical at best. Ballistae, on the other hand, were usable for precision firing, which is accurately reflected by their high hit chance; the rate-of-fire is still borked, though, as they should be able to fire 1 or 2 bolts per minute in such circumstances - and again, that gets into the issue of the one-minute round. The same issue as the heavy crossbow, which by all rights should get 1 or 2 shots per round, as the very heaviest of cranequin or windlass-operated crossbows I've seen still only take 30-40 seconds to span, given a solid 20-30 seconds to take aim and loose in a one-minute round. Unfortunately, EGG extrapolated from the ratio of maximum battlefield rates-of-fire to arrive at his per-round rates-of-fire, despite the fact that much more time is spent aiming in a highly-mobile skirmish situation - which he did account for by reducing rates-of-fire in general, but failed to consider that loading time is only half as much of a hindrance if you're spending half of your time aiming. That and his stubborn insistence on the double standard of "one melee attack roll is the culmination of a minute of back-and-forth, but one ranged attack roll is one shot that consumes one piece of ammunition."

    6. I've always thought some things were wonky about the artillery rules, and it seems like you're way ahead of me in thinking through the details.

      Your very last point is key for me: Frankly the one-minute round was never coherent to me, so I usually don't even consider it as an option, and presume rounds are uniformly one attack/shot -- that is, about 10 seconds each, and in that view the rate-of-fire is sensible once again. If you say that the catapults are shooting a "grape shot" type attack to hit an area effect, that would make sense to me -- although it's hard to interpret giants as doing quite the same thing (better to fold that into the usual D&D man-to-man mechanic).

    7. I totally agree that, as written, the one minute rounds were an abomination - EGG wanted to have his cake and eat it too, borrowing as many rules as possible from Chainmail while playing a very different sort of game. To be perfectly honest, most of the same problems exist in the Chainmail man-to-man rules, and I think the catapult rate-of-fire, range, and area issues stems from the fact that the siege rules are intended for man-to-man play but crept their way into the main 10:1 rules despite being out-of-place in a pitched battle (with the exception, as mentioned, of ballista-type machines, but Chainmail doesn't even specify rules for those to begin with!)... add that to a fetish for pole-arms and the English/Welsh longbow, and a lot of things got thrown out of whack.

      I think that if you rebuilt things from the ground up, you could have a perfectly sensible game with one-minute rounds. It would be a different kind of game than what D&D evolved into, though; heavy on the realism and simulationism and light on the heroic fantasy. That being said, I can totally see the logic of longer rounds that abstractly represent the tempo of a fight; in a real fight, plenty of time is spent jockeying for position, testing the opponent's defenses, and generally keeping one's distance before making the commitment, closing the last couple feet of distance, and attempting to score a telling blow. After that, if neither combatant is defeated in the initial exchange, it can easily devolve into a lengthy period of grappling before either fighter gets an opportunity to make another serious attack. They can also separate and repeat the sizing-up process. All of this can go on over and over again in a boxing or MMA match if the fighters are evenly-matched; though I have no source for this, it seems logical enough to me that the same could happen in a deadly combat, so long as both combatants had sufficient armor to harmless turn aside the multitude of lesser strikes. In such a system, if the fighters started a good distance away, the giant would be able to throw 3 or 4 rocks in my estimation; aggregating that into a single area-of-effect attack would be perfectly fair, in my opinion.

      Of course, with 10 second rounds you are absolutely correct. I'd just be inclined to say that it might take multiple rounds for a pack of encumbered fighting-men to reach the giant if they sighted each other from a distance, during which time the giant would throw a few rocks, gaining a reasonable facsimile of an area-of-effect attack, just split into multiple discrete rolls.

    8. I've noticed that the best fight scenes in movies, and in pro fighting today, you tend to get a lot of incidental or momentary grapples, trips, disarms, locks, knockbacks, etc. It's making me warm up to Zak's Lucky Number Kung Fu and its frequent "special attacks". See also the bear scene in Revenant, which rang very true to me (having, of course, little other knowledge of animal attacks, what animal control and hunters have to deal with, etc)

    9. And I completely agree with Daniel's observation that the wonkiness is inherent in the Chainmail man-to-man rules to begin with (esp.: the lack of any definition for time & distance scale in those rules; so that it was introduced on an ad-hoc basis later in D&D Vol-3).

      Personally, I do like short rounds of action where we can describe very concrete actions (e.g., shot in the abdomen) rather than abstracted scuffling/jockeying.

    10. That's fair. I wasn't so much advocating one minute rounds as much as playing devil's advocate, anyway. While real fighters may only make a couple powerful strikes during the course of a minute, there's a strong pull to make our fantasy pastime more exciting than reality.

  3. Also, a single opponent getting hit by a thrown (or catapulted) rock won't slow the rock down much. Maybe consider a boulder throw like a blue dragon's breath weapon potentially affecting all creatures in line with the giant and its target. Each potential target gets a save to dodge the boulder or take full damage.

    1. Well, maybe -- but that starts to steal the thunder from the Chainmail cannon rules, which was explicitly the rule-reference for lightning. Maybe a grenade-like bounce rule where the rock hits one person nearby would work for me.

    2. I use an "excess damage blows through to next target" for catapults, with Lights getting a 5' wide landing strip and Heavies getting 10' wide. I'm thinking shrapnel more than a single big rock intact at the end.

  4. I think this reveals a general assumption I didn't have before about simulated fights: the circumstances and intelligence by the DM can turn a sure win into a certain defeat and vice versa. For example:

    If you're a dragon, your attack pattern should be to fly up, scaring horses and hirelings (plus the occasional enemy PC) so they bolt apart, then breathe on the largest group you can. Circle around three times, either herding the horse riders or forcing them to dismount and reduce movement so they can't keep up and outmaneuver you. If after three breaths are tapped out you have them on the run, single out the weakest first and claw/claw/bite to victory one by one. If they look solid or recover and regroup, fly away and try again tomorrow until you've melted all their magic items with unlucky item saves. They can straggle back to town over the course of several weeks from the blasted heath you chose to fight them on.

    A Hill Giant should keep away from a large attacking force, ideally letting them track him back to his lair using his "clumsy, stupid mistakes" such as cleaning a kill and not covering it up. The approach to the lair takes advantage of the Giant's height and knowledge of the terrain to give him vision of the approaching party whichever path they take. Of course along each path he's set up some trap: an avalanche of stones or logs, a canyon filled with dry brush he can light and confuse them with smoke and heat (again, scaring horses and hirelings except this time with morale checks). The Giant has tons of boulders lying around - ammunition he has piled up for his use. It doesn't take exceptional cunning to set up ambush points where you get several boulder shots before the party can approach to melee, and where you're covered by at least partial cover / concealment.

    Tucker's Kobolds.

    Then imagine a dragon encountered in a place where it can't fly. Or a Giant encountered roaming on an empty plain carrying a single boulder. Or a band of kobolds spotted in a 10' wide hallway with nowhere to run as the party Fighter dives into their midst to sweep 1 per level per round.

    SO do you think the monster encounter difficulties expect a clever DM, or a monster with at least some environmental advantages, or a monster with absolutely no environmental advantages? Should the environment add stars?

    As an example, should a vampire have an extra star because the DM should play him as a wildly tenacious and intelligent adversary, with several backup plans and escape routes? Or should a DM add a star if he plays the vampire like that? Or take away a star if the vampire fight was staged as a simple "full party ganks on the lone monster until it explodes"?

    1. Well that's a good question. My initial stab at a response would be to treat the earliest inception of the game, a fight between monsters and PCs in a single empty room, as the default. If the monster has taken more time and care to set traps then I'd lean toward that granting an XP bonus of some type. An award per trap would not be bad.

      Now, honestly, I've never been a huge proponent of the Tucker's Kobolds paradigm because of how it changes the base monster in exactly this way. Kobolds are listed as "average/low", and hill giants as "low" intelligence (same as giant beavers, carnivorous apes, etc.), so I don't think many of us would play them like that.

      Dragons are of course a bit more problematic, and I do agree that if they can do a flyby-breath attack that's pretty devastating. It's an interesting tidbit in Chainmail that, "[a] dragon can fly overhead and belch fire down on its enemies at the end of its move", which seems to prohibit a split-move-and-fire, and tactically make sure that the target is within striking distance on their turn.

    2. In short, I like smart and crafty adversaries and situations. But I'm not a champion of arguments that monsters "must" have any particularly fiendish weaponry not listed in their book descriptions. If it's not in the book then it should be worth more, is my gut instinct.