Update #5: Design bibles
I've seen some comments asking what a 'design bible' is, exactly. It's essentially the screenplay or script for the game, but because it is a game, there's a lot of logic and puzzle information built into it. If you're interested in seeing what the game vision was when it came out of my head, and before production began, the design bible is the place to see it.
For each game the bible is usually a little different. For example, the GK1 design bible didn't include a lot of actual dialogue lines -- that was written later in a message editor tool. It did include, however, all the logic and story of 'what happens when' and the puzzle structure.
The GK2 design bible was more like an actual screenplay because we filmed that one with FMV. It includes dialogue. And there was a secondary 'bible' with just puzzle logic.
I've included some jpgs of the GK1 and GK2 design bible pages below. Yes, there is also a GK2 bible... It will appear in the rewards before this is over, I'm sure! Also, $50 pledge tier and more will be getting the design bibles from our new games as pdfs.