| Robert Schwalb |
Probably-not-so-coincidentally, Robert Schwalb, the author of the module, wrote Legions of Hell, one of the other thirds of the Book of Fiends.
To clarify: Of the fiend books that would become the Book of Fiends, Green Ronin first published Legions of Hell by Chris Pramas and then came Armies of the Abyss by Herr Mona. There was a third volume in the works, but it was decided to combine it with an expanded Legions and Armies to create an unholy book of utter wickedness. It was at this stage that I came in. I designed the new demons, devils, and Aaron Loeb (Book of the Righteous)and I together wrote all the new daemon stuff.
As for using the Book of Fiends with FC2, there shouldn't be a problem at all. There are a few minor cosmological differences that can be explained away as more devilish propoganda, and then there's the new arrangement of who rules what--specifically Glasya, but otherwise WotC's Fiendish Codices work damn well with the Book of Fiends series.
Robert J. Schwalb
(PS: We had planned to do a fourth book in the series entitled Lords of the Fiends, but alas, it was not meant to be... It's sad, since my Baphomet was really naughty.)