From publisher blurb:
An unquiet catacomb. Its lacquered walls veined by growth enclose silent alcoves where sarcophagi stand. Reticants pace restless, heeding the Sheen. The Murmur remains.
Condensed to one page for slipping in among other materials, this sandbox-oriented content is intended as an easily absorbed framework for improvisation to be adapted by the user as preferred for a wider setting and specific system.
The content covers map generation on the fly for an abstracted catacomb as well as suggestions for aspects of the locality, including various occupants, active features, reticant organs and spaces beyond.
The catacomb could be detailed using Elaboration: Structure & Surface and possibly Being: More or Less Fantastical Olde Worlde Technologies.