Newell, Gabe (21 de noviembre de 2008). «Gabe Newell Writes for Edge». edge-online.com. Consultado el 22 de noviembre de 2008. «The events are trying to give them a sense of narrative. We look at sequences of events and try to take what their actions are to generate new sequences. If they’ve been particularly challenged by one kind of creature then we can use that information to make decisions about how we use that creature in subsequent encounters. This is what makes procedural narrative more of a story-telling device than, say, a simple difficulty mechanism. ».
