After Kunio and Riki have previously thwarted Yamada's plans, Todo Mamoru apologized for what happened and decided to host a sporting competition where students can compete fair and square. However, this is a cover for his ploy so Reihou High School can reign supreme over other high schools.
The game has 4 different events that players compete in: Yumechicho Cross Country, Obstacle Relay, Camphor Ball, and Battle Royal.
- Yumechicho Cross Country- The event has players running through different sections of the race to reach the goal. Points can be achieved by completing a section before anyone else, hitting opponents, and crossing the finish line. However, players can lose points based on how much time they stay in a section. Any player that loses their energy will be disqualified for the round.
- Obstacle Relay- The objective and rules are similar to Yumechicho Cross Country, but there are obstacles (i.e. Conveyor belts, slippery ice rooms, etc.) that the player must navigate through to the end. (Even though the title says relay, it is not a relay race.)
- Camphor Ball- Players are divided in teams of two to break the giant ball with a preset amount of HP by climbing the pole(s) to the top and punching the ball. The character that punches the ball will be awarded points based on how much damage is being dealt with. The one punch that breaks the ball will be awarded with a bonus. In the end the amount points determines the end round rewards.
- Battle Royal- This event is a fight to the finish where players use their special abilities and whatever weapons they can get their hands on to be the last person standing in the arena. In some variations of the arena, it's possible to throw opponents of it.
- Nekketsu High School: Kunio, Sugata, Nanase, Takamine, Morimoto, and Ichijo
- Hanazono High School: Riki, Saotome, Maeda, Yoshino, Washio, and Shimizu
- School Union: Gouda, Godai, Nishimura, Sawaguchi, Kumada, and Hayami
- Reihou High School: Ryuichi, Ryuji, Kobayashi, Mochizuki, Hayasaka, and Otonashi
- Reihou The Top 4: Kobayashi, Kinoshita, Taira, Mochizuki, Aoki, and Tomiyama
- Reihou Former Student Council: Onizuka, Matsuda, Nakamura, Koga, Ichikawa, Mutou
- This is currently the only Kunio-kun game that was released on Steam and the only one for PS3. River City Ransom Underground (aka Downtown Nekketsu Monogatari Underground in Japan), an official sequel to River City Ransom (aka Downtown Nekketsu Monogatari in Japan), will be the next Kunio-kun game to be on Steam.