While video games have become a popular medium for storytelling, as a more subjective form of game content, evaluation of written or generated narratives remains difficult. We propose a model for game narrative (the combination of story and its discourse) that can be used to both help write game stories, and evaluate existing ones. This model is based on scholarly models of narrative, alongside narrative structuralism. We performed a study of existing video game stories. Stories were broken down into their component events, and data was logged about each event. Results from our analysis show a strong relationship between the ratio of internal "character-driven" events versus external "plot-driven" events and a story's quality. We were also able to make recommendations about overall story event structure, such as limiting strings of external, or "plot-driven", events.