Do the books offer any guidance for PCs who stray from the WBL curve?

Question

Rust monsters are iconic. Nightwalkers less so. But they can both destroy PCs' expensive magic items, placing the party far behind the wealth-by-level (WBL) curve. I might expect that, to compensate, they have increased treasure values (losing multiple 100k gp magic weapons to a nightwalker would require the game to absolutely shower the players with wealth to "make up for"), but this is not the case. Naturally, frontline fighters with lots of metal equipment are most susceptible.

Lots of undead are the opposite. They can give negative levels without affecting PCs' equipment, effectively putting them ahead of the WBL curve. Against intelligent undead, spellcasters with poor Fortitude saves will likely suffer the most negative levels throughout a campaign.

As far as I've read, the DMG doesn't say anything about "catching up" players who spend/lose a lot of money (but not levels), nor the opposite situation. It mentions that an otherwise-weak encounter could be an appropriate challenge if players don't have their equipment, but everything seems to assume that treasure rewards are tied to challenge level, so this doesn't seem like it would "correct" the wealth curve.

Do any of the books have any more to say on how (or even if) PCs should fall back in line with their expected WBL? Or on how to deal with PCs that are consistently not in line with it?

Answer 1

The books’ advice on this subject is rather thin, but it certainly exists:

Your job is to compare the wealth gained from the encounters in your adventure with the expected wealth gain shown on the table above. If your adventure has more treasure, reduce it. If your adventure has less treasure, plant enough treasure not related to encounters to match the value (see Other Treasure, below).

^{(Dungeon Master’s Guide, pg. 54)}

If “the wealth gained from the encounters in your adventure” is actually negative (due to monsters destroying gear), then “your adventure has less treasure,” so you should add more—and, the Dungeon Master’s Guide recommends, you should add it outside of encounters. There isn’t really any commentary offered on why you should do it this way, but we can see that it has the nice effect of both avoiding the problems of trying to balance an encounter for under-geared PCs, and also avoiding the PCs gaining more XP from the encounter and pushing their wealth needs higher.

Of course, there are practical difficulties with this advice in the case of adventurers’ losing a very large amount of wealth as a regular occurrence throughout the adventure—that would imply that random events showering them in incredible wealth just so happen to always fall immediately after such creatures. Realistically, in such cases, you’ll probably have to wiggle around this advice a little. Or, more practically (and more commonly, in my experience), you should avoid such creatures.

---

As an aside,

Lots of undead are the opposite. They can give negative levels without affecting PCs' equipment, effectively putting them ahead of the WBL curve. Against intelligent undead, spellcasters with poor Fortitude saves will likely suffer the most negative levels throughout a campaign.

PCs shouldn’t really ever take a permanent negative level. The point of those rules, in my view, is to force them to get healing, not for them to actually be stuck with the negative level. In general, as a DM, I simply houserule things so the party is always at the same level, because split-level parties are so problematic. As a player, I see permanent negative levels as crippling for a character, and would retire any character who received more than 1 (and probably most who received 1). That is, of course, assuming I’m still willing to play under a DM who caused that to happen.