Chaosium’s efforts to support the Big Yellow Book version of Basic Roleplaying before the new regime took over ended up being a bit of a mixed bag. Devil’s Gulch was horribly botched when it came to the presentation. and Kenneth Spencer’s rather interesting Blood Tide was merely good rather than great because of a sloppy editing job weighing it down. In both cases, there seemed to be a basic lack of professionalism involved in the editing and layout at Chaosium’s end – like the products in question had originated as monographs, and didn’t really get a full polishing-up into a professional-grade product.
Enjoying a much better presentation, and perhaps the best of the Big Yellow Book supplements, was Mythic Iceland. Primarily designed by Brazilian-Icelandic game designer Pedro Ziviani, with the aid of a range of other Icelandic contributors and playtesters, this offers exactly what it says on the tin: a guide to running campaigns in a version of historical Iceland (the baseline assumption is that games will be set somewhere between the foundation of the Alþing assembly and the appointment of the first Christian bishop) where all the myths and legends believed by the Icelandic people are true.
This is a rich blend of genuine folklore derived from sources such as the Eddas, historical details conserved in the Icelandic Sagas, and some of Ziviani’s own inventions to fill in the gap, which he readily admits and highlights. The major gap is that the source material, whilst giving some importance to elves, doesn’t really fill in many details on them, so Ziviani had to flesh them out a lot himself. They are not, at least by default, a PC option, instead being a hidden people that PCs can encounter on adventures.