"seam" in the Prison, Docks, and Begger's Nest (SPOILER)

[GoldDragon]

If, instead of using a torch, you use a sling and Fire bullets on the Burnable Plague Pyres, instead of getting 25 exp, you will get an average of between 500-800 exp, with the lowest being about 425 and the highest amount 2500 (and not very likely, as this requires No crit hits, and doing but 1 pt damage). Bow and Arrow and Crossbow with bolts may also work/ THe Pyres have about 10-15 DR, but not against fire, and 100 HP. Spells don't work, nor does melee damage.

It probably was a bug that never got caught/fixed (or was deemed to difficult to fix without ruining the reward you are supposed to get). It now would likely never get fixed, as 1.69 is the last patch.