It is sometimes said that the whole point of hobbits as protagonists,
for Tolkein, was that they were never meant to go adventuring in the
first place. They were weak, soft, sedentary creatures, with copious
appetites and a great love for civilized niceties.
This
doesn't really fit into the standard model for OSR classes, where you
have a prime requisite, and for demihumans in ACKS at least also a
minimum stat in order to qualify for your race. However, rolling 3d6 in order does
occasionally generate a set of stats which is literally unplayable; the
simplest case would be something like a set where all stats were less
than 9, though it would also be possible to do with a high Con and
possibly a higher Cha, since there's no Cha-only class in Core.
And that's where hobbits should come from: the stat sets that don't qualify for any other class. Give them a racial maximum stats instead of minimum stats, and maybe an inverse prime req bonus, where the more horrible your stats are, the more XP you get. I'm only about half-joking.
I
don't really know what else to give them - probably not great fighting,
some sneaking, decent HD (they do not seem to die as often as one might
expect...), tendency towards ridiculous circumstances... But at the
end of the day, playing a hobbit should be less like playing a ranger
than playing a tourist who, despite his absolute unfitness for adventuring, makes do with a surfeit of either blind luck or divine providence.
Really good saves, I guess.
▼
Tuesday, December 29, 2015
Saturday, December 26, 2015
BaltACKS
One of ACKS' default assumptions, which I've commented on before, is that of the "failing empire", with barbarians at the borders and corruption within. Another of ACKS' standard assumptions it the inland sea, typically modeled after the Mediterranean in Antiquity. But there's another perfectly good inland sea in Europe that gets a lot less attention: the Baltic.
Which, it turns out, is probably a fine model area-of-operations for a DaneACKS campaign. Much more so than the North Sea, with its super-long travel distances and terrible weather. The water-area of the Baltic is about 330 24-mile hexes, which is about a quarter of a 30x40 24-mile hex mapsheet, leaving plenty of room for surrounding lands.
One problem(?) with the Baltic as an ACKS setting is that Scandinavia and environs are, historically, not particularly well-populated. At all. In 1570, already somewhat after our target era, the population density of Sweden was only about 5.2 people per square mile, while that of Finland in 1550 was a mere 2.3 people per square mile. At 300,000 people in an area of 130,666 square miles, you're looking at 60,000 families spread over (roughly) 4 30x40 mapsheets of 6-mile hexes. In 1150, estimates (since at that time there was certainly no census, nor a centralized state to conduct one) place the total population of Finland between 20,000 and 40,000 people, or at most 8,000 families, giving a population density of about 0.3 people per square mile, which in ACKS terms suggests a handful of class VI markets over that entire area. Which is... rough, for adventuring and supply. The rest of the Baltic isn't much better; Gdansk in the 1100s had a population somewhere between 1000 and 2000, which is a class V market. Many of the population centers currently on the Baltic map above weren't even founded until Christianization hit, and population records for pre-Christian settlements (like Forsigtuna, the pre-Christian capital of Sweden) are basically nonexistent. So... I guess there'd be room for some "creative license". On the plus side, such a setting does play very nicely with tribes as the autonomous domain unit, which would be fun.
Which, it turns out, is probably a fine model area-of-operations for a DaneACKS campaign. Much more so than the North Sea, with its super-long travel distances and terrible weather. The water-area of the Baltic is about 330 24-mile hexes, which is about a quarter of a 30x40 24-mile hex mapsheet, leaving plenty of room for surrounding lands.
One problem(?) with the Baltic as an ACKS setting is that Scandinavia and environs are, historically, not particularly well-populated. At all. In 1570, already somewhat after our target era, the population density of Sweden was only about 5.2 people per square mile, while that of Finland in 1550 was a mere 2.3 people per square mile. At 300,000 people in an area of 130,666 square miles, you're looking at 60,000 families spread over (roughly) 4 30x40 mapsheets of 6-mile hexes. In 1150, estimates (since at that time there was certainly no census, nor a centralized state to conduct one) place the total population of Finland between 20,000 and 40,000 people, or at most 8,000 families, giving a population density of about 0.3 people per square mile, which in ACKS terms suggests a handful of class VI markets over that entire area. Which is... rough, for adventuring and supply. The rest of the Baltic isn't much better; Gdansk in the 1100s had a population somewhere between 1000 and 2000, which is a class V market. Many of the population centers currently on the Baltic map above weren't even founded until Christianization hit, and population records for pre-Christian settlements (like Forsigtuna, the pre-Christian capital of Sweden) are basically nonexistent. So... I guess there'd be room for some "creative license". On the plus side, such a setting does play very nicely with tribes as the autonomous domain unit, which would be fun.
Wednesday, December 23, 2015
ACKS: Orcish Assassins
Because sometimes you just need to kill some PCs.
I've been avoiding the issue of Orcs With Class for a while now, because if I make them, then my players will want to employ them or play them. On the other hand, standard-issue orcs are no longer much of a threat (except in hordes ten thousand strong, clad all in sable armor and bristling with swords and spears), and there are rumorings of the Troll Lord having a secret police of assassiny types.
So!
I'm not going to be consistent with building an orc race. Not gonna happen. Orc classes probably get +HD or +Fighting values, as appropriate, and some infravisiony stuff, on a class-by-class basis (that's right, folks - assassins with infravision. Ruh roh).
Orcish assassins are a Fighting 3 / HD 2 / Thief 1 class build.
Prime Reqs: Str and Dex
Requirements: Con 9+
HD: 1d8
Maximum Level: 11
Orcish assassins are sneaky bastards who will kill your PCs. They advance in attack throws at a rate of 1 per level, gain a damage bonus as a fighter of their level, and may cleave once per level per round. They are proficient with all weapons and armor, and may fight with two-handed weapons or a weapon in each hand. They save as fighters of their level, and may use all magic items usable by fighters.
When wearing leather or lighter armor, orcish assassins may Hide in Shadows, Move Silently, and Backstab as an assassin of their class level.
Additionally, orcish assassins are well-versed in the arts of looming, quietly menacing, and other forms of intimidation.
At 9th level orcish assassins can establish terrible orcish murdercults.
Class proficiencies: As Assassin, but remove Intimidation, add Goblin-Slaying, Man-Slaying (as Kin-Slaying... that to-hit bonus is gonna be handy), and Combat Trickery (Knock Down).
XPMath: Racial (2 racial powers - infravision 60' (2), -1 *40 rounded to nearest multiple of 25) -> 50, Fighting 3 with 1 fighting style tradeoff -> 1650, Thievery 1 -> 200, HD 2 -> 1000 -> 2900 XP to 2nd, and weird races do weird stuff above 8th but I don't care.
Expect to see more orc classes soon. Orc fighters are pretty straightforward (fighting 3 with no tradeoffs, HD 2, 50 racial XP for infravision -> 2550 XP to 2nd, max level 12, add Mountaineering and Hard to Kill to class prof list). Orc legates are where this is going to get really exciting (fighting 2 / HD 2 / divine 2, maybe?), and orcsplorers (fighting 3 / HD 2 / thievery 1) should be pretty potent as well.
Or maybe I just found an inspiring piece of art. Nothing to worry about, players. (riiight) |
So!
I'm not going to be consistent with building an orc race. Not gonna happen. Orc classes probably get +HD or +Fighting values, as appropriate, and some infravisiony stuff, on a class-by-class basis (that's right, folks - assassins with infravision. Ruh roh).
Orcish assassins are a Fighting 3 / HD 2 / Thief 1 class build.
Prime Reqs: Str and Dex
Requirements: Con 9+
HD: 1d8
Maximum Level: 11
Orcish assassins are sneaky bastards who will kill your PCs. They advance in attack throws at a rate of 1 per level, gain a damage bonus as a fighter of their level, and may cleave once per level per round. They are proficient with all weapons and armor, and may fight with two-handed weapons or a weapon in each hand. They save as fighters of their level, and may use all magic items usable by fighters.
When wearing leather or lighter armor, orcish assassins may Hide in Shadows, Move Silently, and Backstab as an assassin of their class level.
Additionally, orcish assassins are well-versed in the arts of looming, quietly menacing, and other forms of intimidation.
At 9th level orcish assassins can establish terrible orcish murdercults.
Class proficiencies: As Assassin, but remove Intimidation, add Goblin-Slaying, Man-Slaying (as Kin-Slaying... that to-hit bonus is gonna be handy), and Combat Trickery (Knock Down).
XPMath: Racial (2 racial powers - infravision 60' (2), -1 *40 rounded to nearest multiple of 25) -> 50, Fighting 3 with 1 fighting style tradeoff -> 1650, Thievery 1 -> 200, HD 2 -> 1000 -> 2900 XP to 2nd, and weird races do weird stuff above 8th but I don't care.
Expect to see more orc classes soon. Orc fighters are pretty straightforward (fighting 3 with no tradeoffs, HD 2, 50 racial XP for infravision -> 2550 XP to 2nd, max level 12, add Mountaineering and Hard to Kill to class prof list). Orc legates are where this is going to get really exciting (fighting 2 / HD 2 / divine 2, maybe?), and orcsplorers (fighting 3 / HD 2 / thievery 1) should be pretty potent as well.
Friday, December 18, 2015
ACKS: Custom Magic Types
So there's a Patreon for new and interesting ACKS content, and their first release was today - rules for constructing new flavors of magic (ie, Divine, Arcane, Fae, what-have-you). It doesn't quite go so far as letting you build True Sorcery, but there are still some interesting things I could see people doing with it.
- Psionics are an obvious first candidate (if you're in to that sort of thing, which I'm not particularly).
- Rather than a generic "Divine" magic source with the same effect-type multipliers for all deities, break it down further. Shouldn't Thor's clerics be better at Blast spells than, say, Freya's?
- Though I still ought to finish the Book of ACKSalted Deeds at some point.
- Ooold-school Magic the Gathering (like, Arena-old), with each color having its own set of multipliers on different effects.
- Corny wire-fu martial arts, with touch-range blast and death spells (Poisoned Buddha's Palm, Dim Mak), personal transfiguration (Giant Strength all over the place), protection (Shimmer, Iron Shirt), movement (Air Walk, Swift Sword? Or should we say, Flurry of Blows, or A Thousand Fists?), and healing, optional enchantment (the old Ninja of the Crescent Moon hypnotic pattern) and detection. Spell slots? I think you mean ki points.
- Heck, the sort of 'mythical China' you see in films like Iron Monkey or Crouching Tiger, Hidden Dragon actually checks out pretty well against ACKS' thematic assumptions - empire, threatened by corruption from within (and, less frequently, invaders from without). You just have a few more certified bureaucrats and a few fewer feudal warlords (though depending on the time period...).
Wednesday, December 9, 2015
ACKS: Wilderness Movement Points (Also: Snow, Weasels)
The current "you have n miles of move, times m for terrain, and you can go that far in a day" wilderness movement system works great in homogeneous terrain. In heterogeneous terrain, however, it becomes a pain in the ass. Hence, a simplifying abstraction!
A lovely, grassy, flat 1.5 mile hex of plains or farmland costs one movement point to traverse.
A party in the wilderness has 4 MP/day per 30' of movement speed.
The following terrain types have the the following costs to traverse in movement points:
Snowshoes may be used to negate the movement penalty for snow on the ground (and weigh one item (sixth of a stone) per pair). Skis on snow-covered terrain can reduce its cost to traverse to one category lower than its base (ie, snow-covered mountain is only 3 MP per 2 hexes when traversed with skis in good weather), but weigh one stone per pair. Fighting while wearing skis is sort of hard, and may require Riding (Skis) to move and attack in the same round. Snowshoes and skis are not compatible with livestock, except for dogsleds, riding sabretooth tigers, packmammoths, and other extra-fuzzy beasts of burden specifically adapted to the snow, who count as having snowshoes. Characters with Riding (Skis) may skijor behind such beasts under snowy conditions. I will figure out rules for this later, but it will be fast - as the beast doesn't actually need to carry the rider's weight except on the uphill, skijorers probably count as less encumbrance than their actual weight for determining the overland speed of the beast+skijorer combo.
TODO figure out sled dog prices and availability in markets.
Begin digression
Huh, giant weasels are actually very competitive with grizzly bears and giant boars stat-wise (faster, lower AC, comparable HD, low damage but they latch on so they only need to hit once, best carrying capacity of the three, scent, noted to sometimes burrow into dungeons -> you can probably take them into dungeons). Not trainable as war mounts per DaW:C ("Anyone can ride a giant weasel... once."), but hunting/packweasels (or Beast Friendship henchweasels) would be pretty great.
In the Cons column, if they fail morale they might flip out and try to eat you. They're also pretty pricey, but that sword cuts both ways when you're using them as garrison (Excellent for garrison duty. "The peasants' revolt has reached our gates, sire." "I had hoped it wouldn't come to this, but... release the weasels." "I... I've never seen so much blood, sire.") or you've established a giant weasel breeding program to corner the market.
Apparently "a confusion of weasels" and "a boogle of weasels" are both valid collectives for weasels. If I just came up with a random-ass collective noun for some animal, I wonder how long it would take before google decided it was actually a thing. Your homework assignment for tonight is to use "a conspiracy of cuttlefish" in a sentence somewhere on the internet (seriously, with those w-shaped pupils and adaptive camouflage, they can't be up to any good). I look forward to your reports.
End digression
Right. Where was I before I started thinking about snow and weasels?
If the party doesn't have enough MP to traverse the next hex at the end of the day, keep track of how much of the next hex they still need to traverse. You know, the sensible thing.
I think that's all there is to this. Should make dealing with the sort of overland adventures in mixed terrain we're doing a touch easier.
A lovely, grassy, flat 1.5 mile hex of plains or farmland costs one movement point to traverse.
A party in the wilderness has 4 MP/day per 30' of movement speed.
- 30' -> 4 MP
- 60' -> 8 MP
- 90' -> 12 MP
- 120' -> 16 MP
The following terrain types have the the following costs to traverse in movement points:
- Grassland hills, flat forests: 3/2 (Three per two)
- Wooded hills, barren mountains, swamps: 2
- Forested mountains, icy mountains, forested swamps?: 3
- Truly miserable haunted mountain glacier hellscapes not fit for man: 4
Snowshoes may be used to negate the movement penalty for snow on the ground (and weigh one item (sixth of a stone) per pair). Skis on snow-covered terrain can reduce its cost to traverse to one category lower than its base (ie, snow-covered mountain is only 3 MP per 2 hexes when traversed with skis in good weather), but weigh one stone per pair. Fighting while wearing skis is sort of hard, and may require Riding (Skis) to move and attack in the same round. Snowshoes and skis are not compatible with livestock, except for dogsleds, riding sabretooth tigers, packmammoths, and other extra-fuzzy beasts of burden specifically adapted to the snow, who count as having snowshoes. Characters with Riding (Skis) may skijor behind such beasts under snowy conditions. I will figure out rules for this later, but it will be fast - as the beast doesn't actually need to carry the rider's weight except on the uphill, skijorers probably count as less encumbrance than their actual weight for determining the overland speed of the beast+skijorer combo.
TODO figure out sled dog prices and availability in markets.
Iceweasel: Not Just A Firefox Fork Anymore |
Huh, giant weasels are actually very competitive with grizzly bears and giant boars stat-wise (faster, lower AC, comparable HD, low damage but they latch on so they only need to hit once, best carrying capacity of the three, scent, noted to sometimes burrow into dungeons -> you can probably take them into dungeons). Not trainable as war mounts per DaW:C ("Anyone can ride a giant weasel... once."), but hunting/packweasels (or Beast Friendship henchweasels) would be pretty great.
In the Cons column, if they fail morale they might flip out and try to eat you. They're also pretty pricey, but that sword cuts both ways when you're using them as garrison (Excellent for garrison duty. "The peasants' revolt has reached our gates, sire." "I had hoped it wouldn't come to this, but... release the weasels." "I... I've never seen so much blood, sire.") or you've established a giant weasel breeding program to corner the market.
Apparently "a confusion of weasels" and "a boogle of weasels" are both valid collectives for weasels. If I just came up with a random-ass collective noun for some animal, I wonder how long it would take before google decided it was actually a thing. Your homework assignment for tonight is to use "a conspiracy of cuttlefish" in a sentence somewhere on the internet (seriously, with those w-shaped pupils and adaptive camouflage, they can't be up to any good). I look forward to your reports.
End digression
Right. Where was I before I started thinking about snow and weasels?
If the party doesn't have enough MP to traverse the next hex at the end of the day, keep track of how much of the next hex they still need to traverse. You know, the sensible thing.
I think that's all there is to this. Should make dealing with the sort of overland adventures in mixed terrain we're doing a touch easier.
Monday, December 7, 2015
Wilderness Fatigue, Quantum Caves
I get the feeling that there is something I'm missing with the mid-level wilderness game. I'm not super-excited to prep and run it, and my players don't seem particularly excited to be playing it. On my end there is definitely the possibility of some DM fatigue (supplemented by ordinary work-deadline and performance review fatigue), but I think it's worth considering the pain-points.
- Wilderness travel is slow
- It is slow in game-time because of plate and bad terrain. One good solution to this could be horses... or rocs.
- It is slow in real-time because of counting hexes and multiplying for bad terrain. This is a surprisingly challenging operation to do mentally when crossing multiple terrain types with different multipliers in a single day of travel. Could definitely stand some automation operating on hexographer map files.
- Logistics (estimating how many mules they'll need to carry their water) is not exciting, and also time-consuming.
- Again, automation. You hire an NPC muleskinner, you tell him how many mans, how many days, and how much slop factor you want, I put that in a script, and I tell you a number of mules and a rations-cost.
- Logistics gets a lot more exciting if hungry monsters target the tasty, tasty mules over the guys in plate. The problem here, though, is that if this happens near the end of the journey, your mules are probably mostly empty, and if it happens at the beginning, you can just return home.
- Random encounter results so far have been unsatisfactory
- Part of this is that the default random encounter tables don't really fit my setting. I need to rework them, but for that I also basically need new monsters, and I don't have a good source for monsters in quantity.
- I want to do Western Marches-style per-biome (Blight, Cinderwood, Bjornskog, Bjornfells, Dvagrfells, Mithrskog, Vestrifen, ...) encounter tables, but hexographer doesn't have a good way to draw biome-division lines.
- I should also remember to include natural hazards, "roll on adjacent biome table, no chance of lair", and "roll twice and combine" results on these tables
- I think I've also been confusing the wilderness encounter rate for borderlands travel with the one for fixed settlements in the borderlands, which has led to unusually infrequent random encounters, hence boring travel except when they stumble upon a pre-placed lair (more on that below).
- I really want to check the math on the radius of civilization that gets generated by large settlements.
- I've been failing to use dynamic lairs (again). So far my PCs' routing has taken them through or within spitting distance of some fortuitously-placed lairs, but there are also some that they're basically never going to hit.
- I also want to start placing dynamic nonlairs; dynamic points of interest. Wilderness shrines, circles of standing stones, moon portals, magic pools, barrow mounds, runestones, &c. I call them quantum caves because they're just probability distributions on the random encounter tables until collapsed by observers. No relation to quantum ogres.
Saturday, December 5, 2015
The Nonlinear Effectiveness of Armor Class
Or, why Fighting Style (Shield) and Plate is pretty great.
So you're playing ACKS and you find a ring of protection +1 (a rare and extremely valuable thing). The wizard with AC0 wants it, because having any AC at all would be nice. The fighter with AC10 (plate +1, shield +1, fighting style shield) also wants it, because he thinks AC11 is much better than AC10. The wizard argues that this isn't true, the fighter has enough AC already, and he should stop hogging all the magic items.
(Then the ghouls attack while the party is arguing, but that is neither here nor there)
Who is right?
It turns out the fighter will actually gain (much) more survivability than the wizard will. Here is why.
The more AC you have, the better each point of AC is, on average across all reasonable monsters (up to a point). Let us consider four characters: wizard in no armor (AC0), clumsy thief in leather (AC2), barbarian in chain (AC4), and fighter in plate (AC6). Let us also consider a couple of hypothetical monsters: an orc (THAC0 10+), an ogre (THAC0 6+), a stone giant (THAC0 3+), a woolly mammoth (THAC0 0+), and a great wyrm dragon (THAC0 -3+). If each of these monsters attacks each of these PCs, what is the probability that they will hit?
Looks pretty straightforward - +2 points of AC reduces your probability of being hit by 10%, as we'd expect (up until the monsters only miss on a natural 1, which is what the 0.95s in the bottom left mean).
But what does having your probability of being hit reduced by 10% actually mean for your survival time when fighting this monster? It can mean a lot more than a 10% increase in survival time! Consider AC4 vs AC6 in the case of THAC0 10+. AC4 gets hit about once every 3 attacks. AC6 gets hit once every 4 attacks. So assuming each PC can take the same number of hits, the guy in plate lives 33% longer on average than the guy in chain.
What happens if platefighter gets a shield and Fighting Style, bringing his AC up to 8? Or fighting style and various levels of magic shield and plate for ACs 10, 12, and 14?
AC8 only gets hit by an orc once every 6-7 attacks. He will live twice as long as the PCs in chain, and 1.5 times as long as if he were in plate. At AC10 (shield +1, plate +1, and fighting style), he is hit by an orc only on a natural 20, once every 20 attacks, and will live five times as long as if he were in nonmagical plate with no shield (or about three times as long as if he were in nonmagical plate+shield+fighting style).
This is what I mean by the nonlinear effectiveness of Armor Class. The more AC you have, the more each point increases your life expectancy in combat, up to the point where your opponent needs a natural 20 to hit. Just that one point that pushes them from 19+ to 20+ to hit doubles your life expectancy.
On the flip size, the increase in AC from 0 to 6 only changes your probability of being hit by an orc from 0.55 to 0.25, slightly more than doubling your survival time (assuming the AC0 character has the same number of HP as the AC6 character - an AC0 wizard with d4 HD thus has about a quarter the combat life expectancy in melee of an AC6 fighter with d8 HD). At higher THAC0s, the increase from AC0 to AC6 is even less effective - it means the great wyrm will hit on a 3+ instead of a 2+, which is right around a 5% increase in life expectancy. At that point 6 stone of armor is a liability. Go magic or don't bother.
By comparison, at high THAC0s, even small increases in AC continue to matter. AC12 vs AC14 at THAC0 -3+ is 12 hits per 20 attacks vs 10 hits per 20 attacks is about a 20% increase in life expectancy. Against a stone giant (THAC0 3+), AC 14 survives one and a half times as long as AC12, and twice as long as AC10. Those last couple of points that push your AC up into the low teens are really, really good.
(I strongly suspect that there is some connection here with something like the harmonic progression or some other known sequence, but mathematical insight is failing to strike today)
Incidentally, this also explains why some of my past players felt vehemently that classes who can't use plate shouldn't be in melee, and that if you roll an 18 Dex and a 9 Str, you should use that statblock for a fighter (AC11 with shield and fighting style at 1st level and no magic? Yes please) rather than a thief, explorer, or other dex-based class. This is also, I suspect, why there are basically no spells that increase other peoples' AC in ACKS (except protection from evil, which has some drawbacks). Shimmer (+2 AC for 3 turns) with range touch is probably absurdly good for keeping the monsters from breaking through your fighter-line.
To return to our AC10 fighter and AC0 wizard, the wizard gains, against opponents with THAC0 10+, only 10% survivability by increasing his AC by 1, and that falls as THAC0 increases to the point where it is irrelevant against opponents with THAC0 1+ or better. The fighter, by comparison, doubles his survivability against opponents with THAC0 9+ by increasing his AC to 11, and even against great wyrms with THAC0 -3+, that +1 point of AC increases his expected survival time by about 8%.
Then the question becomes, "Is expected survival time in One Monster vs One PC combat a representative metric of utility in an adventuring context for item allocation purposes?" I think it's pretty arguable - you can't do the party any good if you're unconscious in a pool of your own blood. Likewise, if you live twice as long, you get twice as many chances to attack before dying, and your odds of successfully escaping from combat are much improved too.
This post roughly reflects the state of the dungeoneering fighter metagame in my group - shields are king. I am curious under what circumstances other fighting styles make sense for classes who have access to plate and fighting style shield. I think constructing an ACKS combat simulator and just running like a million trials is probably a better plan that doing math for that, though.
So you're playing ACKS and you find a ring of protection +1 (a rare and extremely valuable thing). The wizard with AC0 wants it, because having any AC at all would be nice. The fighter with AC10 (plate +1, shield +1, fighting style shield) also wants it, because he thinks AC11 is much better than AC10. The wizard argues that this isn't true, the fighter has enough AC already, and he should stop hogging all the magic items.
(Then the ghouls attack while the party is arguing, but that is neither here nor there)
Who is right?
It turns out the fighter will actually gain (much) more survivability than the wizard will. Here is why.
The more AC you have, the better each point of AC is, on average across all reasonable monsters (up to a point). Let us consider four characters: wizard in no armor (AC0), clumsy thief in leather (AC2), barbarian in chain (AC4), and fighter in plate (AC6). Let us also consider a couple of hypothetical monsters: an orc (THAC0 10+), an ogre (THAC0 6+), a stone giant (THAC0 3+), a woolly mammoth (THAC0 0+), and a great wyrm dragon (THAC0 -3+). If each of these monsters attacks each of these PCs, what is the probability that they will hit?
AC | 0 | 2 | 4 | 6 |
THACO | ||||
10 | 0.55 | 0.45 | 0.35 | 0.25 |
6 | 0.75 | 0.65 | 0.55 | 0.45 |
3 | 0.9 | 0.8 | 0.7 | 0.6 |
0 | 0.95 | 0.95 | 0.85 | 0.75 |
-3 | 0.95 | 0.95 | 0.95 | 0.9 |
Looks pretty straightforward - +2 points of AC reduces your probability of being hit by 10%, as we'd expect (up until the monsters only miss on a natural 1, which is what the 0.95s in the bottom left mean).
But what does having your probability of being hit reduced by 10% actually mean for your survival time when fighting this monster? It can mean a lot more than a 10% increase in survival time! Consider AC4 vs AC6 in the case of THAC0 10+. AC4 gets hit about once every 3 attacks. AC6 gets hit once every 4 attacks. So assuming each PC can take the same number of hits, the guy in plate lives 33% longer on average than the guy in chain.
What happens if platefighter gets a shield and Fighting Style, bringing his AC up to 8? Or fighting style and various levels of magic shield and plate for ACs 10, 12, and 14?
AC | 8 | 10 | 12 | 14 |
THACO | ||||
10 | 0.15 | 0.05 | 0.05 | 0.05 |
6 | 0.35 | 0.25 | 0.15 | 0.05 |
3 | 0.5 | 0.4 | 0.3 | 0.2 |
0 | 0.65 | 0.55 | 0.45 | 0.35 |
-3 | 0.8 | 0.7 | 0.6 | 0.5 |
AC8 only gets hit by an orc once every 6-7 attacks. He will live twice as long as the PCs in chain, and 1.5 times as long as if he were in plate. At AC10 (shield +1, plate +1, and fighting style), he is hit by an orc only on a natural 20, once every 20 attacks, and will live five times as long as if he were in nonmagical plate with no shield (or about three times as long as if he were in nonmagical plate+shield+fighting style).
This is what I mean by the nonlinear effectiveness of Armor Class. The more AC you have, the more each point increases your life expectancy in combat, up to the point where your opponent needs a natural 20 to hit. Just that one point that pushes them from 19+ to 20+ to hit doubles your life expectancy.
On the flip size, the increase in AC from 0 to 6 only changes your probability of being hit by an orc from 0.55 to 0.25, slightly more than doubling your survival time (assuming the AC0 character has the same number of HP as the AC6 character - an AC0 wizard with d4 HD thus has about a quarter the combat life expectancy in melee of an AC6 fighter with d8 HD). At higher THAC0s, the increase from AC0 to AC6 is even less effective - it means the great wyrm will hit on a 3+ instead of a 2+, which is right around a 5% increase in life expectancy. At that point 6 stone of armor is a liability. Go magic or don't bother.
By comparison, at high THAC0s, even small increases in AC continue to matter. AC12 vs AC14 at THAC0 -3+ is 12 hits per 20 attacks vs 10 hits per 20 attacks is about a 20% increase in life expectancy. Against a stone giant (THAC0 3+), AC 14 survives one and a half times as long as AC12, and twice as long as AC10. Those last couple of points that push your AC up into the low teens are really, really good.
(I strongly suspect that there is some connection here with something like the harmonic progression or some other known sequence, but mathematical insight is failing to strike today)
Incidentally, this also explains why some of my past players felt vehemently that classes who can't use plate shouldn't be in melee, and that if you roll an 18 Dex and a 9 Str, you should use that statblock for a fighter (AC11 with shield and fighting style at 1st level and no magic? Yes please) rather than a thief, explorer, or other dex-based class. This is also, I suspect, why there are basically no spells that increase other peoples' AC in ACKS (except protection from evil, which has some drawbacks). Shimmer (+2 AC for 3 turns) with range touch is probably absurdly good for keeping the monsters from breaking through your fighter-line.
To return to our AC10 fighter and AC0 wizard, the wizard gains, against opponents with THAC0 10+, only 10% survivability by increasing his AC by 1, and that falls as THAC0 increases to the point where it is irrelevant against opponents with THAC0 1+ or better. The fighter, by comparison, doubles his survivability against opponents with THAC0 9+ by increasing his AC to 11, and even against great wyrms with THAC0 -3+, that +1 point of AC increases his expected survival time by about 8%.
Then the question becomes, "Is expected survival time in One Monster vs One PC combat a representative metric of utility in an adventuring context for item allocation purposes?" I think it's pretty arguable - you can't do the party any good if you're unconscious in a pool of your own blood. Likewise, if you live twice as long, you get twice as many chances to attack before dying, and your odds of successfully escaping from combat are much improved too.
This post roughly reflects the state of the dungeoneering fighter metagame in my group - shields are king. I am curious under what circumstances other fighting styles make sense for classes who have access to plate and fighting style shield. I think constructing an ACKS combat simulator and just running like a million trials is probably a better plan that doing math for that, though.
Wednesday, December 2, 2015
Bundle of Holding: Magical Society: Ecology and Culture: Review
Or, "how many colons can I reasonably put in a post title?".
There is a new Bundle of Holding, Worldbuilding III. I picked up the base bundle, as it contained two of the Magical Society series, of which I have generally heard high praise. I read the first, Ecology and Culture, this evening. This is relevant to a project I am considering to automate worldbuilding at a large scale (in the Dwarf Fortress worldgen tradition, starting with plate tectonics and ending with a hexographer map with stocked 6-mile hexes).
This book is not well-proofread. The most glaring issue is the repeated misspelling of "arctic" to "artic", though the replacement of "band" (as in, "band together") with "ban" is also recurrent.
Their treatment of geology is adequate for fantasy worldbuilding. I was somewhat disappointed with the ecology section (granted, I totally skipped the substantial treatment of magiotrophic organisms due to differing cosmological assumptions about the nature of magic), and am not sure if placing ecology and biomes between geology and weather was the correct organizational choice. I'd've probably gone geology, weather, ecology, biomes, in a causal ordering. Overall this part of the book was decent and I learned some stuff.
The cultures section is strongly reminiscent of Guns, Germs, and Steel, which was an OK book but has attracted substantial criticism. Several assumptions, including the ever-upward Progress of Civilization from hunter-gatherer to pastoral to agrarian to urban (with each better than the last, minus a brief note on magic forsaking advanced societies) and the assumption that war is the near-inevitable result of contact between civilizations, are very GGS. Overall a very instrumentalist, geographically-determinist account of culture - every piece of culture is viewed as an adaptation to an environmental or social stressor. It's not bad advice, but it's also not very interesting. I would have liked to see a treatment of alternate social value-structures, but so it goes. I guess it might be accurate to say that this felt like a fairly shallow treatment of culture to me, with cultures generated likely to be "us in funny hats"; details (food sources, clothing types, deities, taboos) altered but ultimately pretty similar in value-system and ways of thinking to oneself and one's players (which does raise the Tekumel/Rokugan Problem - if the natives are too foreign, I'm going to have a hard time running them. But I have had good fortune with players being interested in strange philosophical groups in my past games).
Anyway, I'm glad I did not pay full price for this book. A decent overview of earth science for DMs, but hardly the 4.5 stars it has on rpgnow. You could probably do about as well with a copy of Guns, Germs, and Steel and a couple of hours on wikipedia. The only thing this book does is save you time.
There is a new Bundle of Holding, Worldbuilding III. I picked up the base bundle, as it contained two of the Magical Society series, of which I have generally heard high praise. I read the first, Ecology and Culture, this evening. This is relevant to a project I am considering to automate worldbuilding at a large scale (in the Dwarf Fortress worldgen tradition, starting with plate tectonics and ending with a hexographer map with stocked 6-mile hexes).
This book is not well-proofread. The most glaring issue is the repeated misspelling of "arctic" to "artic", though the replacement of "band" (as in, "band together") with "ban" is also recurrent.
Their treatment of geology is adequate for fantasy worldbuilding. I was somewhat disappointed with the ecology section (granted, I totally skipped the substantial treatment of magiotrophic organisms due to differing cosmological assumptions about the nature of magic), and am not sure if placing ecology and biomes between geology and weather was the correct organizational choice. I'd've probably gone geology, weather, ecology, biomes, in a causal ordering. Overall this part of the book was decent and I learned some stuff.
The cultures section is strongly reminiscent of Guns, Germs, and Steel, which was an OK book but has attracted substantial criticism. Several assumptions, including the ever-upward Progress of Civilization from hunter-gatherer to pastoral to agrarian to urban (with each better than the last, minus a brief note on magic forsaking advanced societies) and the assumption that war is the near-inevitable result of contact between civilizations, are very GGS. Overall a very instrumentalist, geographically-determinist account of culture - every piece of culture is viewed as an adaptation to an environmental or social stressor. It's not bad advice, but it's also not very interesting. I would have liked to see a treatment of alternate social value-structures, but so it goes. I guess it might be accurate to say that this felt like a fairly shallow treatment of culture to me, with cultures generated likely to be "us in funny hats"; details (food sources, clothing types, deities, taboos) altered but ultimately pretty similar in value-system and ways of thinking to oneself and one's players (which does raise the Tekumel/Rokugan Problem - if the natives are too foreign, I'm going to have a hard time running them. But I have had good fortune with players being interested in strange philosophical groups in my past games).
Anyway, I'm glad I did not pay full price for this book. A decent overview of earth science for DMs, but hardly the 4.5 stars it has on rpgnow. You could probably do about as well with a copy of Guns, Germs, and Steel and a couple of hours on wikipedia. The only thing this book does is save you time.