Expendable
Additional credits
Press A, B, Left, A, B, Right, B, A, Down, R during game.

Additional lives
Press A, B, X, Y, L, R, Up, Down, Left, Right during game.

First person perspective
Press L, Left, R, Right, X (x2), Down (x2), R, L during game.

God mode
Press Up, Down, Left, Right, L, R, Left, Right, Start during game.

Grenades
Press Down (x5), Up (x4), R during game.

Instant victory
Press L, R, L, R, Left, Right, Left, Right, Y, X during game.

Select level
Press Up, Down, Up, Down, Up, Down, Left, Right (x2), Y during game.

Shields
Press Up, Down, Left, Right, X, Up, Down, Left, Right, Y during game.

Skip level
Press Y (x2), X (x2), L, R, Down (x2), Up (x2) during game.