Decretum Umbra is publicly known as a traveling circus, though a handful of individuals know that it is much more than that.
Translating to roughly "Decree of the Shadows," Decretum Umbra is a fairly old organization dating back well over 150 years. It is led by members of House Mavanix who split from the main branch of the house early in the house's inception. It was founded by Carmilla Mavanix as a historical research organization with an emphasis on secret societies. It didn't evolve into a circus until it came under control of its current leader, the enigmatic Barbas Mavanix. The second-in-commands are Freya Mavanix, Marvani Mavanix, and Zacriel Mavanix. There are numerous other non-family associates who work under the family. These primarily include various entertainers such as clowns, gypsies, beast tamers, and so on.
The group is constantly moving, making its whereabouts often unknown until they advertise a show at some remote location (usually small villages). Often, these shows serve as a cover for other seedy operations that remain out of the public's sight.
Beneath the surface, the group specializes in intelligence gathering, magical studies, and artifact theft. Working at Barbas's behest, the group quietly assists as an umbrella organization in the rebuilding of House Mavanix's vast pool of resources.