The Shades of the Uskwood is a cabal of albino druids who call the dark heart of the Uskwood of Nidaltheir home. While the Shades are dedicated to the natural power of the dark wood, they also revere Zon-Kuthon. This reverence is symbolized by the wearing of an Umbrae-Token, a fetish of hair, twigs and blood. For this worship, these dark druids are rewarded with the ability to cast spells beyond the abilities of their uncorrupted brethren.1 They are led by Eloiander of Ridwan, who is also a member of the Umbral Court, the council that rules that dark nation.2
For additional as-yet unincorporated sources about this subject, see the Meta page.