Gravalax

Gravalax is an Ultima agri-world, the Ciaphas Cain first-novel stage where the 12th Valhallan, T'au diplomats, and a genestealer cult shared a polite border planet. This pin sits in its own named system rather than under a generic Ultima dump.

Cain and Jurgen spent For the Emperor trying not to start a third war while Amberley Vail took notes. Gravalax is not a T'au sept, not a hive, and not a later Cain joke-world with no diplomats. The PDF learned that hospitality toward xenos comes with extra claws.

Gravalax still matters as Cain's named opener. Unofficial fan summaries keep the gravalax-system parent and refuse to relabel the pin a sept world or a Valhalla sister colony.