A major limitation of today's computer games is the shallowness of interactions with non-player characters. To build up relationships with players, NPCs should be able to remember shared experiences, including conversations, and shape their responses accordingly. We believe that progress in AI has already reached the point where research on using NLP and large KBs in games could lead to important new capabilities. We describe our Listener Architecture for conversational games, which has been implemented in a toolkit used to make short experimental games. Episodic memory plays a central role, using analogical reasoning over a library of previous conversations with the player. Examples and scale-up issues are discussed.