Man, if there is anything that makes me want a story bible, it is the writing of a sequel.
This is something I've only partially attempted once before. On my mission I wrote sequel outlines for two books following the Jakeson storyline, and actually put a few thousand words into one once I got back, but it didn't get very far. I think I am now discovering why.
A sequel seems to be an entirely different beast from the first book. A first book has to worry about a lot of things, from the basic details of the world to the introduction of the main characters and their traits. The sequel doesn't have to worry about that, but it does have to worry about developing them further. So your character did a lot of awesome stuff in the last book. What's he doing now? How has he changed, or what could possibly challenge him after what he went through in the last book? How will he change further now that he has new things to face?
Even more intimidating is the fact that I now have to base everything on a foundation provided by the last book. I find myself constantly questioning whether a detail should have gone in Wolfhound, or if it is okay to put it in Badger instead. Were the characters and development foreshadowed enough in the last book? It has made me want to go back and do one more edit solely to provide that solid basis, though I'm not sure if that's a good idea or not.
So in summary, this is a new experience that may or may not be driving me crazy. Anyone surprised?