The Experts Talk to Xbox.com at E3

Fable® is a game that's long been in development, and all the while, anticipation has been growing for what promises to be a truly innovative roleplaying game (RPG). The screenshots and early previews have whetted our appetites, but now the game is close to appearing on store shelves.

How is it looking? We went to the source—legendary designer Peter Molyneux and A.I. programmer Adam Russell—to get their word on what's sure to be a must-have item on gamers' Christmas lists this year.

Xbox.com: Fable was first announced two years ago. How much has the project changed since then? Are you surprised at some of the directions the game took?

Molyneux: Actually, it has probably been around for much longer than that, in the sense that Dene and Simon [Carter] and I have been discussing doing an RPG for years. In some fundamental ways, it has not changed a bit. The ability of the main character to morph and change, according to the way the game is played, and the way the world reacts to you through the expression system have been constants. Perhaps the most surprising direction was how long it took to perfect the fighting system. We spent much longer than we expected to get it right, and we must have tried hundreds of permutations before we finally felt that it was right.

Oh, that's gotta hurt!

Xbox.com: How has the A.I. developed? What were some of the challenges you faced in getting non-playable characters to behave the way you wanted them to?

Russell: I think our hardest challenge in working on the A.I. in Fable has been making sure that the many and various system features implemented actually result in a rich canvas of detailed and tangible game content for the player to interact with—and that it all hangs together and makes sense. This is a long-term problem in game A.I., particularly in those titles which contain open-ended and unscripted gameplay situations … more so when those situations involve simulation of ordinary human behavior … and especially when the player's perspective is not working at the level of whole armies, cities, or whatever, but instead is "close up" to the behavior of individual people in small groups. Fable contains a lot of this kind of stuff.

For a long time, everybody in the A.I. team works on their own little patch of game code or script in isolation—making characters, for example, fight or go to sleep every night in a continuous day cycle, trade with the player while manning their market stall, perform a job, approach the player to ask for help as part of a story vignette, lie await in ambush, and so on and so on. Then, you put all this together in combination. Inside your towns, you have a constantly changing time of day. You also have, let's say, 100 different behaviors that villagers might want to perform and an unknown number of independent story scripts running alongside the A.I., each adding their own goals and actions. On top of that, you've got the player running about talking to people, attacking them, standing obstinately in doorways, flirting with the womenfolk, bringing in people from another town, persuading villagers to quit their job and join him as followers, and so on. In other words, you've got a whole world of pain for the A.I. team! It's been a long haul, but somehow, we've pretty much cracked this difficult nut.

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