This paper describes the design of a competitive game to support "offense" and "defense" teams as they develop and improve their scenarios and plans about possible crisis situations. The threats are used as an evaluation mechanism for the resulting plans. The game uses a Computer Mediated Communication System over a time from several weeks to several months, allowing players to participate asynchronously. Each new cycle of improved planning is stimulated by "intelligence leaks," changes in resources available to both sides, and selected new information. The game may easily be adapted to competitive companies, or a competitive situation between man and nature such as a flood or earthquake. The structure and applications of the game are discussed, and the initial field trials are described.