This report examines how games can be used to communicate and teach complex system structures. In collaboration with the total defence research institute, a game is being developed to introduce operational analysts to the Swedish total defence. The target group for the game lacked both experience in systems thinking and total defence, which is why the game was considered a good method to test. The study has a design science research approach and used Arnold and Wade's systems thinking matrix as the basis for the game's learning objectives. The development of the game is largely based on methodology taken from serious gaming, war games and game pedagogy. The result of the studies was that a number of points of interest for game development linked to complex systems are identified. Among other things, the result strengthened the idea of ​​using games as an educational tool. The study also demonstrated certain difficulties with games and complex systems, where sometimes challenges were connected to creating a game that fairly depicts even the hidden relationships within a system.