Agent data
Press Up, Down, B, R, Left, L, Right, A, R, X, Up, R.
Alien data
Press X, L, B, L, Down, Y, R, Right, A, Left, R, Y.
All Combat Skills Training levels
Press X, Up, L, Left, Y, A, R, B, Right, R, X, B.
All weapons at full power
Press Up, Down, A, X, R, Y(2), Left, B, L(2), Right.
Better guns
Get better guns by using Agent K.
Boss mode
Press R, Y, Down(2), A, L, Left, X, Right, Y, R, L.
Cheat Mode
Enter one of the following codes at the title screen when "Press Start Button" appears. The screen will flash to confirm correct code entry. Note: Enabling a cheat will disable saves. Also, the Combat Skills Training levels will not be available, unless its code is used.
Defeating Bosses
When fighting the Bosses, it is just as easy to use your pistols than any other gun.
Do Not Drop Weapon Levels
Press Down, Up, A, X, Down, Up, A, X, L(2), X, B.
Faster speed
If you want to be faster, use Agent J.
Full Area Effect
Press Left, A, Y, Up, A, Down, X, L, Left, R.
Full Beam
Press Left, B, Y, Right, L, X, Left, R(2), Y.
Full Bolt
Press Left, Right, Up, Down, L, B, Y, R, Left, Down, X(2).
Full Homing
Press Right, Up, X, L, Left(2), L, Left, B, Left.
Full Spread
Press L, R, B, L, Down, Up, L, Right, Left, A.
Invincibility
Press Right, A, R, Y, Up, L, A, Left, L, B, A, R.
Level select
Press R, Y, Left, B, X, L, Left, Up, A, Down, L, X.
Making Of FMV sequences
Press B, L, R, B, Y, Down, X, A, Right, L, A, Up.