How Small Changes in a Game's Story Can Make a Huge Difference

I recently wrote to the author of a book I love, Think Like a Programmer.  I had wanted to ask some questions related to using the book for one of our first year classes. But it turned out that V. Anton Spraul also happens to be interested in stories in games, the topic of my thesis.

Leave me alone, I'm reading. / Hey Christine 

We had some interesting discussion on the topic after he read our Foundations of Digital Games paper on coherent emergent stories. I thought that some of his suggestions of how this sort of system could work were so spot on, I wanted to share them here.  So, with Anton's permission, here is what he said:

So I'm intrigued by your idea, especially by how it could be employed without the player knowing -- using a "tension" value to control the type or volume of music in a scene, for example. What if a game gradually lowered tension over time outside of character interaction or combat, so that a scene would actually play differently just because the player took a long walk before a key confrontation? Cool stuff. Or a game with Bioware-style dialogue interaction where certain choices were not always present, and not because certain information had previously been discovered or not, but because of the emotional state of the player avatar at that moment, as influenced by prior events? Perhaps ultimately, a game could be made which always arrives at the same scene, but the outcome of the scene is largely controlled by prior actions in a way the player wouldn't predict--so maybe the player can only shoot the final boss if he or she is angry enough to do it. (I was let down by the endings of the otherwise brilliant Deus Ex and Deus Ex: Human Revolution because they didn't depend on anything that happened five minutes before the end of the game.)

I like the tension example especially.  We had pictured using different lighting, or camera angles, depending on the path the player took previously.  For example, maybe the ending of the game is the same either way, such as the princess returning to the kingdom after "taking care of" the threat of the nearby dragon.  Simply knowing that the player befriended the dragon and learned its behaviour was a result of it protecting its child would already cause a different interpretation of the culminating scene than if the player had slayed the dragon.  But adjustments in lighting, for example, might emphasize this.  The idea that additional small changes based on tension could reflect the urgency with which the player acted seems all the more interesting!

This kind of approach is meant to allow players to have an effect on a story's outcome without the need to create much (or anything) in the way of additional assets.  I think the potential is enormous.