Raiders of the Lost Tomb
Chwinga are small nature spirits whose nature has been debated by sages for centuries (fey or elemental?). They appear as tiny humanoids with black skin, black curly hair, and white facemasks with tribal style designs. They speak by making clicking noises. Generally they are not a threat to explorers, but are curious and may steal from backpacks and stores. If they do they leave behind something they deem to be of equal value – nuts, uncut gems, a pretty shell, etc.