The game SO LONG SUCKER was designed in the United States in 1964 with the aim of showing how potentially unethical behavior necessary for winning was inherent in the game's incentive structure. Sessions with East Asian participants, however, led to very different game dynamics in which collaborative rather than antagonistic behaviors occurred. This confirms that the course of a simulation game run is determined by more than its rules and roles. The participants' personalities, skills, personal histories, and preexisting relationships also play a role. Furthermore, the unwritten rules of social behavior that the participants have been socialized into, their culture, is of crucial importance. This article uses experiences with a mix of U.S. and Taiwanese participants to discuss the interaction of written and unwritten rules in determining game dynamics. The suitability for international classroom use of this game, and others, as a vehicle for drawing lessons about culture is argued. (Contains 3 figures.)