At the "Vault" screen of Disc 1, press Square, Triangle, Circle Square.
At the "Event Center" screen of Disc 1, press Triangle, Circle, Square.
At the main menu of Disc 2, press Triangle, Circle, Triangle, Circle.
At the main menu of Disc 2, press Circle, Triangle, Square, Circle.
At the main menu of Disc 2, press L1 + L2 + R1 + R2.
At the main menu of Disc 2, press Triangle, Circle, Triangle(2), Square.
At the "Code Archive" screen of Disc 2, hold Square + Circle and press Triangle(2).
At the main menu of Disc 2, press Start.
If you line up the first four volumes of the Underground series CD packages spines, you will see the following code: Press Circle, Triangle, Square, Triangle(2), Circle(3) to reveal a secret URL (http://www.playstation.com/hiddenprize), username (underground), and password (insider). The hidden prize...well go there and find out!
| Fighting Force | |
| Infinite Health | 80096060 017C |
| Infinite Gun | 80066946 0010 |
| Infinite Rocket Launcher | 80066942 0004 |