A side-effect of exposure to certain se-borne algal byproducts, especially the sort that might concentrate in stagnant corners of a sea-side port; the cause of this condition is a cyst that briefly forms in one’s back following exposure to such chemicals. This cyst works to aggravate the back, causing inflammation and great pain if the sufferer labors too hard or strains their back too much, which in turn aggravates the muscle further in an endless cycle of discomfort and pain. Many a lazy (or merely overworked) dockhand will claim to have this disease to buy themselves a few easy days of work and an excuse to self-medicate, but the sickness is indeed a real one, best treated by consumption (or inhalation) of certain intoxicating plants.

Exposure to the cyst-causing chemicals, especially in and around dirty sea-water common near busy settlements, forces humanoids to succeed in a DC 11 Constitution save or be infected. While the cyst is present, infected humanoids have their Encumbrance capacity halved, and generally feel some pain when doing any sort of lifting. The effect lasts 2d6 days while the cyst dissolves, but the effect can be ignored with daily consumption of intoxicating, pain relieving herbs.