Gabe Newell on procedural narrative

"To come up with a theory for how to do narrative in a multiplayer game we started by looking at the players’ different behaviors – exactly how they’re playing, what their actions are, where they move.

We tried to note as many interesting contexts of their actions as possible. Are they moving together as a group or are they splitting up? Is their mouse jerking around a lot, or are they interacting smoothly? Are they agitated or are they relaxed? How much damage are they taking? How accurate is their shooting?

Then, using all that data we tried to come up with a model to tell us how the player is faring in the game.

The data can tell if a player is comfortable or if they are starting to be overwhelmed. Once you have that concept, then you can start to create pacing and events in response to the player."

Gabe Newell Writes for Edge