Hailing from 1993, Castles Forlorn‘s original form was as a boxed set adventure supplement for Ravenloft. In fact, it was one of the last products of the game line’s earliest version – making reference not to the 1994 revised boxed set, but to the original Realm of Terror box from 1990 and the 1992 Forbidden Lore box which expanded it somewhat. The other products extensively referenced therein are the Monstrous Compendium volumes (generally the core ones and the Ravenloft appendices) and Van Richten’s Guide to Ghosts.
Indeed, to a certain extent the adventure is a worked example of how you apply the Guide to Ghosts, since the castle which gives the module its title is absolutely stuffed with ghosts given extra depth using techniques and ideas along the lines of that book’s suggestions. Wait, though, isn’t the title Castles Forlorn? Why, yes it is -for the castle at the heart of the broken realm of Forlorn is three in one, existing as it does in three time periods at the same time, so characters venturing therein may, through their experiences in those time periods, have a shot at unpicking the terrible story underlying the fall of the realm to the Dark Powers.