Kaido Battle 2: Chain Reaction is the second game in the Kaido Battle PlayStation 2 spin-off series of Shutokou Battle. Throughout the courses, the player can check the rival's info, sponsor's info, lover's info, change and tune up the car or check the prize. Cars can be bought new or in used cars shop, along with various parts for your car such as engine parts, air cleaner, turbo kit, cooling module, tires, and such. For aesthetics and dress up, things such as car color, wings, and other visual gadgets can be installed. Battle modes include Speed King mode, CA King mode and SP King mode. Additionally, two players can race in Versus battle on a split-screen. Unlike its predecessor and successor, the game was not released in North America.

The story is set after Kaido Battle/Tokyo Xtreme Racer Drift, Tokyo Xtreme Racer Zero and 3, but before Kaido Battle : Touge No Densetsu.

The year 20XX.

Mountain passes became high-tech circuits, equipped with safety devices. Now recognized among street racers, it became the ultimate stadium for car battles. Another day begins and racers gather at the circuits, all trying to be the best. The roar of the engines echo through the mountains...

Since Koukami defeated Hamagaki, the former Emotional King, new racers appeared and new circuits opened (Akagi, Zao...) and Koukami is now the new Emotional King.

Some Slashers have returned, such as MMC Ooaza and Haruna Guardian, some have moved like Lonely Wanderer, and others have come.