Deer Hunter

Go to the main menu, choose "Credits" options, then press the
following button combinations while the credits are displayed:
After entered the code, you will see a message.

Unlock levels:
Triangle + Circle, Down, Left, Up, Right

Unlimited ammunition:
Square + X, Left, Square + X, Square + X

Invisible to animals:
Triangle + Circle, Left, L2, Down, Down

Easy shots:
Triangle + Circle, Left, L2, Up, Down

Run:
Triangle + Circle, L1, Up, Up, Up

Jump to nearest animal:
Triangle + Circle, L1, Left, Left, Up
Press L3 + R3 to jum to the nearest animal.

Giant animals:
Square + X, Square + X, Left, Left
Press L3 + R3 to jump to the nearest animal.

Shoot other hunters
Triangle + Circle, Square + X, Square + X, Square + X
Shoot the other hunters with your bow