Surface-eye

Deep below the great dwarven city of Harginhold, ten thousand dwarves tirelessly mine for valuables ores – iron, copper, silver, gold, platinum, mithril, and adamantine. Fumes in these mines, while not lethal, are quite harmful to creatures who can see in the dark. Those who have long-term exposure to these fumes are at risk of developing surface-eye, a condition in which one loses their darkvision.

Cause and Symptoms

About ten percent of creatures with darkvision are affected by the fumes that seep into the mines underneath Harginhold. The origin of the fumes is not known, and each time a leak is plugged, another appears not long after. Those affected describe a sensation of burning that affects their eyes and a gradual dimming of their vision when in the dark. Their vision in daylight or other well-lit areas is seemingly unaffected.

Effects on Dwarven Society

One of the most reliable ways to earn a living in Harginhold is to work the mines below. Since not all dwarves are affected by surface-eye, most decide it is worth the risk.

Cure

In 329 OA, a physician living in Engrirhold discovered that the bile harvested from Ankhegs could be used as one of several reagents to concoct a cure for surface eye. This medicine is only effective for those who have not fully lost their darkvision.
The Engrir clan has greedily guarded the identity of the other reagents, making them the only source of the cure. Combined with the increased demand for the bile, which is still used in several mining processes, the elixir has made the Engrirs exceptionally wealthy over the past decade.
While news of a cure was initially met with joy and optimism by the miners, soon turned to anger and resentment when it became clear few of them would ever be able to afford it. Civil unest has steadily grown in Harginhold, with members of the wealthier clans becoming victims of street violence.