Past debris flow events, like in Bondo (2017) and Brienz (2005) in Switzerland have been heavily covered in the (Swiss) media, illustrating how destructive such events can get. Protection measures play an important role in dealing with natural hazards. Debris flows are considered to be very rare, complex and multidimensional processes. Imagining and foreseeing the course and progression of a debris flow as well as estimating the potential damage and the influence of protection measures is a difficult task. Serious games offer a possibility to simulate these kinds of situations. With the MurGame, we have developed an application for natural hazard prevention. In the three-dimensional, interactive game, a village is created by selecting different objects, such as residential buildings or schools. Debris flow simulations show, which buildings would be destroyed and what damage would occur in the event of a debris flow. Different protection measures can be implemented to protect the village and their effectiveness can be monitored during the simulations. After the event, it is necessary to evaluate which measures offer the desired protection, what they may cost and how the needs of the population are met. The MurGame can be played online at www.murgame.ch.