Artificial Intelligence Design in a Multiplayer Online Role Playing Game

In this paper, we describe our experiences and lessons learned utilizing a rule-based system for implementing the AI in a multi-player online role playing game called Mythic. We explain how we organize AI rules, how those rules are assembled from a database, how sets of rules are assigned to game entities, the different sets of inference rules, the different phases of inference rules, and how we manage facts used by the inference engine. We also review some of the history behind the Mythic project, where it is headed, what a rule-based system is and why we chose to use one for our project. The result of our project is a design that allows us to have diverse AIbehavior and flexibility to reuse code to create new behaviors, but may prove to be inefficient if implemented on systems with a large number of players or many AI controlled game entities.