All Weapons
Enter "NSRLS" as a password.
Maximum ammunition 
Enter "MMLVSRM" as a password.

Play as General Plastro 
Enter "PLSTRLVSVG" as a password.

Play as Vikki 
Enter "GRNGRLRX" as a password.

Play as Tin Soldier 
Enter "TNSLDRS" as a password. Note: Enter this code after activating another character code to create a Tin version of that character.

Test information 
Enter "THDTST" as a password.

Mini mode 
Enter "DRVLLVSMM" as a password.

Reverse weapon selection 
While playing a game, hold B and press Z to cycle through weapons in reverse order.

Restart level 
While playing a game, hold L + R + C-Down to return to the starting location of the current level.

Level passwords 
Level             Password 
Attack            LNLGRMM 
Spy Blue        TRGHTR 
Bathroom       TDBWL 
Riff Mission  MSTRMN 
Forest           TLLTRS 
Hoover Mission   SCRDCT 
Thick Mission     STPDMN 
Snow Mission     BLZZRD 
Shrap Mission     SRFPNK 
Fort Plastro        GNRLMN 
Scorch Mission    HTTTRT 
Showdown         ZBTSRL 
Sandbox           HTKTTN 
Kitchen              PTSPNS 
Living Room        HXMSTR 
The Way Home [Note] VRCLN 
Note: This password also unlocks all characters in multi-player mode.