Kessen (決戦, "Final battle") is a real-time tactics video game produced by Koei and published by Electronic Arts. It was a launch game for the PlayStation 2 in Japan and North America. It was initially the only real-time wargame game available for the PlayStation 2.
It is a real-time tactics game set in feudal Japan, focusing upon a conflict between the eastern Tokugawa clan and western Toyotomi clan (with Ishida Mitsunari as the Toyotomi's guardian and protector) shogunates at the end of Sengoku Jidai. Tokugawa Ieyasu served as the primary representative for the Eastern forces where the Western army changed leaders based on the results of select key battles.
Although it is, for the most part, historically accurate, the game contains a number of "what-if" scenarios, for example, if the Western forces are victorious at the Battle of Sekigahara (historically an Eastern victory).