This subseries contains materials related to the development of role-playing games and are arranged into sections according to the line: Chill, DC Heroes, Role Aids and City State of the Invincible Overlord (Advanced Dungeons & Dragons compatible), Underground, and general role-playing game materials and additional titles.

Materials include notes, manuscripts, proposals, outlines, correspondence, maps, graphic design papers (paste-ups, proofs), invoices, articles, advertisements, artwork, transparencies, miniatures, microcassette, newsprint, photos, negatives, slides, 3½” floppy disks, and realia.

Note that some manuscripts were stored with pages out of order; extreme care was taken to restore pages in order, however some materials could not be identified with complete certainty. In cases where manuscripts had multiple drafts/versions, the first, last, and any unique drafts were maintained.