Infinite Points
     Go  to  a  rock wall in a desert level. Shoot the rocks, and your
points  will  go  up  with every shot. If shooting in one area doesn't
work, shoot an edge.

Level Skip
     Pause  the  game,  hold  L2,  then  press  Up, Down, Left, Right,
Triangle,  X,  X,  Triangle,  Right,  Left, Down, Up. Unpause the game
while still holding L2.

Super Weapons
     While  playing, quickly press Up, Down, Left, Right, Triangle, X,
Square.

Weapon Power-Up
     Pause  the  game,  hold  L2,  then  press  Up, Down, Left, Right,
Triangle, X, Square. Unpause the game while still holding L2.

Extra Characters
     At  the  Options screen, hold L1 + L2 + R1 + R2 and press Circle,
X, Triangle, Circle, Circle, X, Square.