Quickly press L1, R2, L2, R2, L2, Triangle, Circle, Triangle, Circle, then hold L1 and press Start at the "Press Start" menu to unlock max power mode. The sound of a gunshot will confirm correct code entry. Max power mode allows you to start with all weapons and unlimited ammunition. Note: The code must be entered before demonstration mode begins.
Trial mode
Quickly press Up, Down, Down, Right, Right, Right, Left, Left, Left, Left, then hold Triangle and press Start at the "Press Start" menu to unlock trial mode. The sound of a gunshot will confirm correct code entry. This mode allows any level in the game to be played. Note: The code must be entered before demonstration mode begins.
Sudden death mode
Quickly press L2, R2, L2, R2, Circle, Triangle, Circle, Triangle, then hold L1 and press Start at the "Press Start" menu to unlock sudden death mode. The sound of a gunshot will confirm correct code entry. Note: The code must be entered before demonstration mode begins. Sudden death mode allows opponents and your character to be killed with one hit. Alternately, Quickly press L2, R2, L2, R2, Triangle, Circle, Triangle, Circle, then hold L1 and press Start at the "Press Start" menu.
All multi-player characters
Quickly press Up, Down, Down, Right, Right, Right, Left, Left, Left, Left, then hold Circle and press Start at the "Press Start" menu. The sound of a gunshot will confirm correct code entry. All the Bosses as well as the engineer and a few army characters will be unlocked in multi-player mode. Most of the Bosses have odd guns and may not be able to back up against walls or roll. Alternatively, successfully complete the game under the easy and normal difficulty settings. Note: The code must be entered before demonstration mode begins.
Sudden death mode
Quickly press L2, R2, L2, R2, Circle, Triangle, Circle, Triangle, then hold L1 and press Start at the "Press Start" menu to unlock sudden death mode. The sound of a gunshot will confirm correct code entry. Note: The code must be entered before demonstration mode begins. Sudden death mode allows opponents and your character to be killed with one hit. Alternately, Quickly press L2, R2, L2, R2, Triangle, Circle, Triangle, Circle, then hold L1 and press Start at the "Press Start" menu.
Max power, sudden death, trial modes
Successfully complete the game under the hard difficulty setting to unlock max power, sudden death and trial modes.