Expendable

Pause the game play and press the following button combinations:

1st person view: Press L, Left, R, Right, X, X, Down, Down, R, L.
Bonus credits: Press A, B, Left, A, B, Right, B, A, Down, R.
Bonus lives: Press A, B, X, Y, L, R, Up, Down, Left, Right.
God mode: Press Up, Down, Left, Right, L, R, Left, Right, Start.
Grenades: Press Down, Down, Down, Down, Down, Up, Up, Up,Up, R.
Instant win: Press L, R, L, R, Left, Right, Left, Right, Y, X.
Shields: Press Up, Down, Left, Right, X, Up, Down, Left, Right, Y.
Skip stage: Press Y, Y, X, X, L, R, Down, Down, Up, Up.
Stage select: Press Up, Down, Up, Down, Up, Down, Left, Right, Right, Y.