Undying Fellowship of Ylstikeme

The Undying Fellowship of Ylstikeme is an ancient interplanar society of archaeologists, sages, and historians that seek to gain as comprehensive an understanding of the Multiverse's history as they possibly can. Despite its name, the Fellowship consists of numerous loosely connected cells spread far and wide across the planes; Ylstikeme itself holds no particular significance other than being the plane on which the Fellowship was founded.

Membership is restricted to those with knowledge of the Librarium, a spell taught only to those who have performed the Fellowship's initiation rites. It grants a near-eidetic memory for historical knowledge, heightened resistance to informational and memetic hazards, and the ability to telepathically share one's historical knowledge with others who know the spell. It also magically forbids those who know it from sharing the Fellowship's secrets (including its very existence as a multiplanar organization) with the uninitiated. The knowledge granted by the spell always includes the numerous secret ciphers and initiation rites that mark one as a member of the Fellowship, as well as others added by the founders of whichever cells the initiator belongs to.

Though its existence is a closely guarded secret, those of the Fellowship (commonly referred to as "librarians") are expected to spread their knowledge as widely as possible. This often requires them to cloak their words in myth and superstition, so as not to give away the source of their extraplanar wisdom. Whenever a group or belief system on an otherwise primitive plane has a surprisingly accurate perspective on its place in the Multiverse, the Fellowship is as likely as not to be the cause. On more advanced planes, or when dealing with other planeswalkers, the Fellowship will be open about its local cell's nature and purpose but feign ignorance of any cells on other planes.