Sean K. Reynolds said:
A Theory About Peasants (and other non-adventurer NPCs)
I've been thinking for a while about a more formalized method of determining character level for NPC-class characters in a community. After some conversations with the folks on the D&D-Tech list (a small private list for the finer points of D&D rules discussion) a while ago, I thought of the foundations of a theory.
The Typical Peasant
Let's assume that a human peasant "becomes" a Com1 upon reaching age 20 (I could start it at 15 or 18, but this makes my calculations easier in the long run). The life of a typical peasant is not easy; they work long hours, don't get a lot of food, and don't have a lot of safety and security in their lives. In a way, they are like modern-day people who manage to scrape by every month with enough money for rent, food, and basic supplies, but usually don't have anything left for luxuries. Each month is a matter of survival. In a way, each month is like an "encounter" with a dangerous situation--starvation and death.
Encounters With Death
When viewed in this fashion, a month for a commoner is like a combat encounter for an adventurer. There is a risk and a reward, and some are harder than others. Like any encounter, it should have a CR. Now, most peasants manage to live month to month, and a month doesn't use 20% of the peasant's available resources, so the month's CR is going to be somewhat arbitrary (and will fluctuate over the course of the year). But let's assume that the month's CR is equal to the peasant's character level (using the assumption that "life doesn't throw you anything you can't handle), so a brand-new peasant Com1 would have months that are CR 1. (Note that as the peasant gains levels, running the same farm isn't going to get harder just because he's better at running a farm, so the monthly CR should stay at CR 1).
XP For An Encounter
A 1st-level party would gain 300 XP for defeating a CR 1 encounter, so a 1st-level peasant would gain 300 XP for defeating an encounter with a CR 1 month. However, the peasant normally isn't at an instant life-or-death risk at any one point (unlike an adventurer), so I'm going to reduce that award by half, to 150 XP. Furthermore, the peasant is probably married and sharing the work with a spouse (just like adventurers share the work in a fight), so we should divide that XP between the two of them, for 75 each. If we multiply that value by 12 months, we get 900 XP for the peasant. To make my future math much easier, I'm going to say that averages out to about 1,000 XP in a year.
Progression After A Year
So after a year, the peasant has 1,000 XP -- enough to reach level 2! Because XP awards for CR 1 encounters remain the same until the party level reaches 7th level, the peasant is going to continue to earn XP at a rate of 1,000 per year until he reaches 7th level. A character reaches 7th level at 21,000 XP, which (at a rate of 1,000 XP per year after age 20) puts the peasant at age 41, which is middle age, and getting toward the upper limit for typical medieval humans. In short, you can determine a peasant's level by subtracting 20 from his age, multiplying by 1,000, and checking the XP chart.
Beyond 7th Level
At 7th level, a CR 1 encounter only gives 263 XP, so the peasant is only earning 877 XP per year, so it takes him about 8 years (to age 49) to reach 8th level (instead of 7). At 8th level, a CR 1 encounter only gives 200 XP, so the peasant is only earning 667 XP per year, and it takes him 12 years (age 61) to reach 9th level. At 9th level and beyond, characters don't normally earn XP for CR 1 encounters, so the peasant doesn't earn any more XP for a typical month, which means that unless there is an entire year of hardship he's not likely to gain any more levels. Given that age 61 puts him well into old age, he's not likely to survive a harsh year anyway.
Other NPC Classes
What applies to commoners applies equally well to adepts, aristocrats, experts, and warriors; their challenges are of a different sort, but few are instantly life-threatening (even warriors that are non-mercenaries such as city guards rarely have to deal with anything more dangerous than a drunk, and those that do end up with more XP because of it), and so this gradual increase in levels works for them as well.
Nonhumans
Although the term "peasant" isn't totally appropriate, this system works just as well for nonhumans as well as humans. Because the XP awards trickle off at the middle levels, the increased lifespan of these nonhumans doesn't generate extremely high-level peasants. Those "peasants" who live long and end up reaching levels above 9th probably had some interesting encounters along the way (anyone who lives 100 years or more in an elven forest or dwarven subterranean city probably has had to deal with monster attacks at least once) and could probably eke out a few more levels.
PC Classes
You could apply this system to characters with PC classes as well, but I would severely restrict their ability in one of two ways: One, either reduce the XP awarded by 50% again, as these adventuring classes don't get much out of not adventuring. Two, only allow people to acquire NPC classes with this method, so your retired Ftr4 captain of the guard is going to have to pick up warrior or expert levels if he wants to advance, simply because he's not getting the right kind of experience to advance as a fighter.
