PS1 | Submitted by GamesRadarInner Level E
Enter "HEYBUDDY" as the password. After that, options to select a stage, section, invincibility, all weapons, and removing the pause text will appear.
Enter "HEVYFEET" as a password.
Enter "MAXPOWER" as a password.
Beat the game and then enter the password "1MORELVL".
Full Pause Screen
Enter "THEPRESS" at the password screen