Training by playing is believed to be an effective strategy for learning. Training games combine educational and technological techniques that help learners to get involved, collaborate and learn in a practical and interactive way. Collaboration is inherent to software requirements elicitation which involves customers, users and developers to achieve an overall goal. In this article, a game entitled TREG that simulates various activities in software requirements workshop is proposed. The trainee interacts with Non-Player Characters and according to the trainee's choice the game reenacts a specific scenario. The social simulation in the game is based on the branching stories genre. Each branching node is described using a scenario-based template. The game was prototyped in Second Life, a virtual world that gives the possibility to create an immersive collaborative educational experience. © 2009 IEEE.