A second chance
According to the legend, Dread Velsparge, Daemon Prince of the Myriad Hands, plunged into the Tarakhen Sea in a blaze of scarlet flame, throwing the whole world into ruin.
During certain years, people in Akgku claim to observe a green flame coming from the sea and erupting upward. It can be observed from a distance of two days’ journey or more. After burning for a considerable time, the flame disappears.
—Falklyde Wodinger, Haraconian scholar, in route to wondrous Udross and legendary Akgku.
A plague has hit the local area.
In humans it affects only the most vulnerable, the children and the very old, and even than it's little more than a summer cold. 24 hours of sniffles and then it's gone, barely noticeable really.
To sheep however it is fatal and the whole economy of the area is in serious trouble. If this keeps up the area could well be facing famine.
Somebody (enter the PCs) must find the rare herbs needed to make a cure.