It’s hard to pick just one and it’s also hard to decide upon what criteria I should judge which is my favourite. Some systems are a joy, some a chore. Some backgrounds, likewise. It can be fun to create something new and it can be fun to work on something with a lot of reach. It can be great to turn a property from its form as a book, film or comic into a game. Each game has its own microcosm of different factors and can be a favourite in a different way.
I’ve worked on Dungeons and Dragons and that’s quite a feather in your cap (at least when you’ve worked directly for Wizards) but the various incarnations of D&D, even 5th Edition, just really aren’t my cup of tea and while I enjoy Dark Sun and Planescape, the more vanilla fantasy settings and ideals typical of D&D are frustratingly hackneyed and cliche (not that that’s bad, it’s just hard and not that enjoyable to write for).
Breathing new life into BLOOD! was fun, an old, relatively obscure horror game that we always loved, but it wasn’t really ‘mine’.
Agents of SWING was a passion project, and I enjoy writing for FATE (though less so the current edition). Working together all the threads of the action/adventure series of the 60s and 70s was a fun challenge.
Working on SLA Industries was great and I and Dave Allsop had good synergy and mutual understanding in the work I did for SLA. Unfortunately that joy has been lessened by falling out with one of the other people involved and the semi-butchering of the main book I did for them. A similar thing – editorial interference I didn’t like – happened in work I did for Call of Cthulhu.
Creating the semi-official Neverwhere RPG, adding to the lore and ideas, creating an innovative system and then giving the whole shebang away for free (terms of the agreement) was a huge amount of fun and that game – in its third edition – may be my most favourite, if least profitable, thing I’ve ever done.
But then, there’s still the tentacle porn…