Nobunaga no Yabou: Ranseiki (Nobunaga's Ambition: Chronicle of Chaos) is a turn-based strategy game developed and published by Koei, released in Japan in 2002. The game introduces a new era of Nobunaga with full 3D, real-time battle scenes, featuring warriors, cavalry, flag bearers, battlefield terrain, and towering castles. It allows players to control vast battles with real-time changes in the battlefield, creating a dynamic and immersive experience. Players can choose strategic positions for troops based on military class and use special commander skills for powerful attacks, such as assaults or three-stage gunfire.

The game features seven distinct factions, including temples and shrines that sparked uprisings, ninjas skilled in espionage, and indigenous forces, all influencing the path to unifying Japan. With over 1,400 warlords from Nobunaga's birth (1534) to the eve of the Battle of Sekigahara (1599), the game offers 10 scenarios showcasing the turbulent Sengoku period.

Additionally, the game includes a warlord editor, allowing players to create custom warlords and exchange them using a PlayStation 2 memory card.