Maximum Stats
Change your name to DAMAX (case-sensitive) in the status menu.

$999,999
Change your name to PLAYA (case-sensitive) in the status menu.

Deleted Saved Games
Change your name to ERAZE (case-sensitive) in the status menu

Quick Death on Reihou's Roof
At the left corner of Reihou's Roof, if you're carrying someone and they jump off straight down then they will fall down through an invisible hole and dies. (Works even on Slick)

Secrets
Easy Reputation Increase.
To quickly and easily increase your rep, simply run into a wall. Every time you do this, the game will give you +1 to your rep.

Fight Riki/Kunio
Start the game in 1 player mode only not 2 player mode and go outside the 2nd factory and you will fight your ally

Fight Slick with the Dragon Twins and Onizuka
Must have 3 allies that are not Mochizuki,Taira,or Kinoshita

Fight the Dragon Twins with Gouda
Joining You Without any Enemies in the Beginning When Gouda asks to join you, say no and go meet Godai and say yes to his question, then go to Reihou High's last floor

Get Godai
Have Gouda in your team and a good reputation

Get Gouda
Talk to the girl before the spa, then the girl outside the fish store, then at the 1st place of the last shopping place

Get Hayasaka
Beat Mochizuki 5 times and Hayasaka will appear(requires high reputation for him to join you)

Get Kobayashi on Your Team
Must have high reputation the 1st time you fight him

Get Kumada
Decline Himada's offer to join you and come back and fight everyone and Kumada will be there

Get Maeda
Play as Riki only in the beginning and go to Sherman Park

Get Mochizuki
Have High Reputation

Get Sonokwa and the Senridai Bombers
Play as 1 player without Riki and beat the Senridai Bombers anywhere 3 times then go to the 2nd place in the game and beat everyone there

Get Sugata
Play in 1 player mode as Kunio then he will be either at the beginning place or at Sherman Park when Kinoshita appears there

Get Taira
Have High Reputation

Meet Todo
Must have a reputation of either equal or higher to getting Kobayashi unto your team, he is located at the 2nd shopping place in the game

Meet Todo
Second Time Must have meet him the first time and this time he appears at Reihou's gate after you beat Gouda once